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Bobolink

The Bobolink (Dolichonyx oryzivorus) is a medium-sized New World blackbird in the family Icteridae, notable for its striking sexual dimorphism, elaborate song, and extreme long-distance migration between North American breeding grounds and South American wintering areas.^[1] Breeding males display bold black underparts contrasting with a white back and scapulars, buff hindneck, and black cap, a plumage unique among North American birds, while females and non-breeding adults are streaked brown for camouflage in grasslands.^[2] The species name oryzivorus, meaning "rice-eater," reflects its consumption of grains, particularly rice, during southward migration, which has historically led to conflicts with agriculture in the southern U.S. and overwintering regions.^[1] Bobolinks breed in open grasslands and hayfields from the Great Plains eastward to the Atlantic coast and southern Canada, where males perform bubbling, jangling songs in flight displays to attract mates and defend territories.^[3] They undertake one of the longest migrations of any songbird, traveling up to 12,500 miles round-trip annually, navigating partly by stars and magnetic cues to reach rice fields and marshes in Bolivia, Paraguay, and Argentina for winter.^[4]^[5] Populations have declined sharply—by over 50% in some areas since the 1960s—primarily due to habitat loss from agricultural intensification, early hay mowing that destroys nests, and conversion of prairies to row crops, though the species remains classified as Least Concern globally by the IUCN owing to its large overall range.^[3]^[6] Conservation efforts, such as delayed mowing incentives for farmers, aim to mitigate these pressures and support recovery in fragmented breeding habitats.^[7]

Taxonomy

Classification and Phylogeny

The Bobolink (Dolichonyx oryzivorus) is classified in the order Passeriformes and family Icteridae, the New World blackbirds, which encompasses about 107 species characterized by adaptations to diverse New World habitats from forests to grasslands.^[8] It comprises the sole species in the monotypic genus Dolichonyx, named from Ancient Greek dolikhos ("long") and onyx ("claw"), referring to the species' notably elongated hind claw adapted for perching in grassy substrates.^[9] The specific epithet oryzivorus derives from Latin oryza ("rice") and vorare ("to devour"), denoting the bird's documented consumption of rice and grains, particularly during southward migration.^[9]^[1] No subspecies are recognized, reflecting limited genetic variation across its range consistent with a single, cohesive population.^[10] Molecular phylogenies based on mitochondrial DNA, such as cytochrome-b sequences, resolve Dolichonyx within Icteridae's core clades, specifically aligning it closely with Xanthocephalus (yellow-headed blackbird) in a lineage of grassland-associated blackbirds distinct from tropical troupials and orioles.^[11]^[12] Comprehensive species-level analyses using multiple genetic markers confirm five primary lineages in the family, with Dolichonyx nested in the "blackbird" group alongside genera like Agelaius, supporting monophyly of these taxa through shared synapomorphies in vocalization and plumage patterns.^[11] These studies, drawing from sequences of over 100 icterid specimens, indicate divergence times within Icteridae on the order of 10-20 million years ago, calibrated against avian fossil benchmarks.^[12] Evolutionary reconstructions position Dolichonyx as derived from tropical Icteridae ancestors, with adaptation to open temperate grasslands representing a shift from forested or savanna niches prevalent in the family's South American origins.^[13] This grassland specialization correlates with Pleistocene habitat expansions via megafaunal grazing and fire regimes, though direct fossil evidence for Dolichonyx is absent; Pleistocene icterid remains, such as those of extinct cowbird-like forms, affirm the family's presence in North American open habitats during that epoch.^[14] Phylogenetic mapping of breeding latitude shows temperate icterids like the Bobolink embedded within predominantly tropical clades, implying multiple independent colonizations of northern grasslands facilitated by post-glacial environmental changes.^[13]

Etymology and Naming

The common name "bobolink" emerged in late 18th-century American English as an onomatopoeic rendering of the male's distinctive spring song, phonetically captured as "bob-o-link" or the earlier variant "bob-o-Lincoln." This imitative origin reflects auditory mimicry of the bird's vocalizations, with the earliest documented use of "bob-o-Lincoln" appearing in a 1774 diary entry by John Adams, predating the standardized form around 1796.^[15]^[16] The scientific binomial Dolichonyx oryzivorus traces to Carl Linnaeus's 1758 description in the 10th edition of Systema Naturae, initially classified as Fringilla oryzivora among the finches. The modern genus Dolichonyx, introduced by William Swainson in 1827, derives from Ancient Greek dolikhos ("long") and onyx ("claw" or "nail"), denoting the species' notably elongated hind claws adapted for perching on grasses. The specific epithet oryzivorus combines Latin oryza ("rice") with vorare ("to devour"), referencing observations of the bird foraging on rice and grains, especially during southward migrations through agricultural areas.^[9]^[1]^[17] Early European and American accounts employed variant common names tied to the bird's appearance, habitat, or diet, such as "rice bird" for its depredations on rice fields in the southeastern United States and "reed bird" from its association with grassy meadows. These designations, noted in 19th-century ornithological texts, underscore the species' economic impact as a perceived pest in grain crops prior to protective conservation measures.^[3]^[17]

Description

Physical Morphology

The Bobolink (Dolichonyx oryzivorus) is a medium-sized icterid with a total body length ranging from 15.2 to 20.5 cm.^[18] Males typically weigh 34–56 g, while females weigh 29–49 g, reflecting sexual dimorphism in mass.^[18] The wingspan averages 29.2 cm, featuring nine functional primaries that taper to points, facilitating efficient long-distance flight.^[19] The tail comprises 12 rigid, sharply pointed rectrices, contributing to a relatively elongated posterior profile.^[20] The bill is short and conical, measuring approximately 1.0–1.2 cm in length, with a structure enabling precise gleaning of insects from vegetation and ground substrates.^[21] This bill shape aligns with adaptations in icterids for handling small arthropods and seeds, as evidenced by dietary analyses showing predominant invertebrate consumption during breeding.^[21] Legs and feet are adapted for terrestrial foraging in grasslands, with elongated tarsi and notably long hind toenails that aid in scratching and stability amid dense vegetation at heights of 6–15 cm above ground.^[21] The skeletal framework includes a lightweight passerine build, with fused clavicles forming a furcula to support pectoral musculature for powered flight, though specific dissections on D. oryzivorus emphasize general avian traits rather than unique modifications.^[22]

Plumage and Sexual Dimorphism

Adult male bobolinks in breeding plumage exhibit striking sexual dimorphism, featuring predominantly black underparts and head, contrasting with white scapulars on the back, a white rump, and a buff-yellow hindneck.^[2] ^[23] This bold coloration develops through a prealternate molt completed by late spring, rendering males conspicuous during territorial displays in grassland habitats.^[24] In contrast, adult females in breeding plumage display a buffy brown overall tone heavily streaked with dark brown on the upperparts and underparts, providing crypsis against grassland backgrounds for nest protection.^[2] ^[25] This streaked pattern aligns with adaptive camouflage in open fields, where observational studies note reduced detectability by predators.^[26] Both sexes undergo a complete postbreeding prebasic molt into non-breeding (basic) plumage, resulting in similar buffy, streaked appearances that obscure sexual differences; males lose their black feathering and acquire female-like tones by late summer.^[2] ^[24] Juveniles emerge with plumage transitional to adult basic, featuring finer streaking and softer buff hues, molting into formative plumage shortly after fledging.^[20] This seasonal convergence in plumage supports crypsis during migration and wintering in grassy areas, with specimen analyses confirming the molt sequence's role in habitat matching.^[24]

Distribution and Habitat

Breeding Range

The Bobolink (Dolichonyx oryzivorus) breeds primarily across central and eastern North America, extending from southern Canada southward to the central United States.^[27] Breeding populations span from Nova Scotia westward through the prairie provinces to British Columbia, though the core range concentrates in the northern and midwestern United States.^[28] Densities peak in Midwest grasslands and hayfields, where over 25% of the global population occurs in Canada from Saskatchewan to Quebec.^[29] Marginal breeding occurs in isolated western populations, including central Washington, northeastern Nevada, northern Utah, eastern Arizona, Kansas, and north-central Kentucky.^[27] Historical expansions westward into prairies followed irrigation and cultivation in the Great Plains, but current distributions show contractions linked to agricultural intensification.^[27] Breeding Bird Survey (BBS) data from 1966–2015 document significant declines averaging 1.8% annually across the range, equating to a 53% population reduction, with steeper losses in eastern regions.^[29] North American population estimates from BBS data approximate 9.7 million breeding individuals, concentrated in high-density areas of the upper Midwest and Great Lakes region.^[30] Atlas surveys, such as New York's Breeding Bird Atlas, confirm occupancy in 65% of blocks during 1980–1985, with subsequent data indicating localized declines of 6–90% in states like Vermont and agricultural Midwest counties.^[31]^[32]

Non-breeding Range

The non-breeding range of the Bobolink (Dolichonyx oryzivorus) is confined to southern South America, extending from approximately 8°S to 32°S latitude.^[26] This includes the pampas grasslands of northeastern Argentina, eastern Uruguay, Paraguay, and Bolivia, as well as savannas and agroecosystems in southwestern and northwestern Brazil.^[33] ^[34] Within Argentina, occurrences are documented along the southern edge of the range, with historical banding and sighting records confirming concentrations in Entre Ríos, Corrientes, and Buenos Aires provinces.^[27] Bobolinks preferentially occupy flooded grasslands associated with major river systems and large marshes, alongside agricultural habitats like rice fields where they forage on seeds.^[29] ^[35] These birds largely avoid northern tropical regions, such as the Amazon basin, with limited vagrancy northward of 8°S.^[36] Tracking data from geolocators and banding recoveries indicate intra-seasonal movements during the non-breeding period, with synchronized shifts southward or to resource-rich areas in response to habitat phenology and food availability.^[37] ^[38]

Habitat Requirements

Bobolinks require open grassland habitats characterized by moderate to tall vegetation for breeding, including native or tame prairies, hayfields, and lightly grazed pastures with grass heights typically ranging from 10 to 166 cm and visual obstruction readings of 6 to 75 cm.^[39] Nest site selection favors dense grasses and forbs providing overhead cover, with average vegetation heights of 33 to 77 cm directly at nests and moderate litter depth of 5 to 39 percent for concealment.^[39] Empirical studies indicate preferences for sites with 17 to 65 percent grass cover, 3 to 50 percent forb cover, low shrub density (≤22 percent), and limited bare ground (≤38 percent), which enhance nest survival by reducing predation exposure.^[39] Microhabitat features include higher soil moisture at nest locations compared to surrounding areas, often in proximity to wetlands or moist meadows that support invertebrate prey abundance essential for foraging adults and nestlings.^[39] Bobolinks depend on agricultural landscapes such as alfalfa and cool-season grass hayfields for nesting, where vegetation structure mimics native grasslands, but suitability diminishes under intensive mowing regimes that remove cover prior to fledging, as documented in studies showing reduced densities in early-cut fields.^[40] Larger patches exceeding 10 hectares are selected to minimize edge effects, with nest success correlating positively with patch size and distance greater than 50 meters from woody edges or roads.^[40] During non-breeding periods in South American pampas and rice stubble fields, habitat use shifts to areas with standing crops or residual vegetation providing seed resources, though specific microhabitat data remain limited compared to breeding grounds.^[39] Overall, reproductive success in empirical field studies is highest in idled or late-hayed grasslands with heterogeneous structure, underscoring the role of vegetation density and moisture in habitat quality across life stages.^[40]

Migration

Patterns and Timing

The northward spring migration of bobolinks (Dolichonyx oryzivorus) from South American wintering grounds to North American breeding areas occurs primarily from April to May, with males preceding females by several days to weeks to establish territories and attract mates, as documented by banding recoveries where initial arriving flocks consisted almost exclusively of males.^[41]^[21] Southward fall migration commences after breeding concludes, with adults first undergoing a complete post-breeding molt in staging areas such as freshwater marshes from late June through August, followed by departures from late July to early September in mixed-sex and age flocks.^[42]^[43] These southerly movements involve extended non-stop flights sustained by pre-departure fat accumulation, enabling transoceanic endurance without intermediate return stopovers characteristic of shorter legs.^[1] Geolocator deployments across breeding populations reveal fall migration durations of 3–4 months including staging, contrasting shorter spring transits of 5–6 weeks, while stable isotope signatures in feathers confirm molt-migratory transitions tied to dietary fat-loading phases.^[44]^[41] Bioenergetic analyses of captive bobolinks quantify rapid lipid deposition rates—up to 0.5–1.0 g/day—optimizing energy stores for these demanding flights, with fat comprising over 90% of migratory fuel.^[45]^[46]

Routes and Stopovers

Bobolinks primarily follow a southeastern migratory corridor during southward travel, progressing from breeding areas through the eastern United States to Florida, where they undertake trans-Gulf of Mexico flights to reach Caribbean islands such as Cuba, Jamaica, Hispaniola, and Puerto Rico for refueling.^[41] These island stopovers provide essential wetland and grassland habitats for energy replenishment before continuing to northern South America, with geolocator studies confirming this pathway as dominant for fall migration.^[47] A critical refueling site en route is the Llanos grasslands spanning Colombia and Venezuela, where birds make protracted multi-week stops to exploit seasonally abundant resources, as evidenced by light-level geolocator deployments revealing consistent use across populations.^[41] ^[40] In the southern United States, particularly Florida's coastal marshes and rice fields, migrants pause to forage, though habitat fragmentation from agricultural intensification and development poses risks to these limited sites.^[3] Northward routes often incorporate greater overland components across Central America, minimizing extended oceanic crossings beyond necessary Gulf of Mexico segments, with radar and geolocator data indicating flexibility to evade adverse weather.^[48] Tracking studies from 2013–2017 document inter-annual variability in pathways, driven by meteorological conditions and individual condition, underscoring the adaptive nature of these circuits rather than rigid corridors.^[47] While some individuals utilize inland Mexican and Central American grasslands as stopovers, the prevalence of Gulf crossings persists, exposing birds to heightened energetic demands and predation vulnerabilities.^[49]

Behavior

Breeding Biology

Bobolinks employ a polygynous mating strategy, with males arriving first on breeding grounds to establish and defend territories through aerial displays and singing, thereby attracting multiple females per territory.^[50]^[17] Females select nest sites within these territories and construct open cup nests on the ground amid dense grasses, laying clutches of 4–7 eggs, typically 5–6.^[21]^[29] Incubation lasts about 11–12 days and is performed exclusively by the female, commencing with the laying of the penultimate egg.^[51] Nestlings receive biparental care, with both sexes provisioning food, leading to fledging after 10–11 days.^[26] Bobolinks are predominantly single-brooded, though females may renest following nest failure.^[40]^[52] Nesting success remains low in mowed hayfields, where mechanical operations destroy over 50% of nests in some studies, yielding overall success rates below 20%; early-season haying can result in near-total failure (e.g., 99% in one Vermont-New York analysis).^[39] Empirical monitoring links higher fledging rates to taller vegetation (>50 cm), which enhances concealment from predators and delays exposure to mowing, contrasting with reduced survival near edges or in short-grass areas.^[53]^[54]

Foraging and Diet

During the breeding season, the Bobolink's diet consists primarily of invertebrates, comprising approximately 57% of stomach contents by volume from analyses of northern U.S. samples, with the remainder being seeds and vegetative matter.^[55] ^[56] Insects form the bulk of this invertebrate portion, including pest species such as grasshoppers, beetles, and larvae, which provide essential protein for provisioning nestlings.^[57] Seeds, including weed seeds, supplement the diet but are secondary to insects during this period.^[57] In non-breeding periods, including migration and wintering grounds, Bobolinks shift to a predominantly herbivorous diet, with stomach and regurgitation analyses from rice fields in Argentina revealing 97% plant matter, of which 55% is rice grains—reflecting the species' specific epithet oryzivorus (rice-eater).^[58] They preferentially consume rice in the soft "masoso" stage and other grains, with minimal insect intake observed in such habitats.^[59] Bobolinks employ gleaning techniques to capture insects from grass stems and foliage while perched or in flight, and probe the ground for seeds and prey.^[55] ^[3] They typically swallow items whole and often wipe their bills on vegetation afterward, foraging solitarily or in flocks except during nesting.^[55] Diurnal by habit, they may feed nocturnally during migration to accumulate fat reserves.^[57]

Vocalizations and Communication

The male bobolink produces two primary song types, termed alpha and beta, each consisting of 25–50 distinct notes arranged in a fixed sequence lasting approximately 3.5 seconds on average.^[60] The alpha song features introductory notes followed by interior phrases and concluding warbles, while the beta variant is shorter and structurally similar but abbreviated.^[61] Spectrographic analyses reveal songs composed of syllable-like figures grouped into non-random phrases, with acoustic properties including bubbling trills, high-pitched tinkles, and buzzy elements that vary in frequency modulation and duration.^[62] These songs function in both territorial defense and mate attraction, with playback experiments demonstrating that alpha songs elicit stronger aggressive responses from rival males, such as increased singing rates and approaches to speakers, compared to beta songs, supporting their intrasexual role in rival deterrence. Beta songs, by contrast, appear more closely associated with intersexual contexts like courtship displays.^[63] Males deliver songs from perches or during fluttering flight displays over breeding territories, often at high rates to establish dominance.^[60] Song dialects exhibit geographic variation, with spectrogram-based studies of recordings from multiple sites in North Dakota and Minnesota showing high similarity within local populations (mean coefficient of 0.44) but low inter-population overlap, indicating distinct phrase sequences and figure combinations tied to specific localities.^[62] These dialects likely facilitate population-specific recognition and are culturally transmitted, as young males acquire them from established breeders in their first season.^[62] Females produce chatter-like call series, including "chunk" notes during nesting activities, alongside shorter alarm and contact calls to signal threats or coordinate with mates.^[60] Both sexes use a soft "pink" call year-round for flock communication and during flight, with males occasionally incorporating song elements in aerial predator responses.^[60]

Ecology

Predators and Parasites

Nest predation is the primary cause of reproductive failure for bobolinks (Dolichonyx oryzivorus), with rates influenced by habitat structure such as proximity to forest edges, where attacks occur up to 190 m into pastures.^[25]^[40] Documented avian predators include raptors such as Northern Harriers (Circus hudsonius) and hawks (Buteo spp.), while corvids like American Crows (Corvus brachyrhynchos) also target nests.^[64] Mammalian predators comprise foxes (e.g., red fox, Vulpes vulpes) and weasels, alongside snakes that prey on eggs and nestlings.^[65]^[66] Predation incidence varies regionally, remaining low in Oregon but elevated in Wisconsin, as determined from field monitoring.^[26] Camera trap deployments have documented specific predator identities at bobolink nests, revealing higher risks in open or edge habitats with reduced vegetative cover.^[67] Bobolinks face brood parasitism from brown-headed cowbirds (Molothrus ater), which lay eggs in host nests, but empirical rates are low and geographically variable; for example, 0% of 422 monitored nests in New York showed parasitism.^[50] Haemosporidian blood parasites, including Plasmodium lineages responsible for avian malaria, infect bobolinks during migration, with shared strains detected between breeding grounds in North America and stopover sites like the Galápagos Islands.^[68]^[69] These parasites exhibit diverse communities in sampled individuals, potentially reducing host fitness through chronic effects on blood cells and immune function, though quantified impacts on bobolink survival remain understudied relative to predation.^[70]

Interspecies Interactions

Bobolinks engage in heterospecific competition with other grassland birds for breeding territories and resources in shared habitats like hayfields and pastures. Assemblages including the Eastern Meadowlark (Sturnella magna), Savannah Sparrow (Passerculus sandwichensis), and Grasshopper Sparrow (Ammodramus savannarum) exhibit structured dynamics driven by interspecific attraction and aggression, with bobolinks defending territories against both conspecifics and other species through displays and chases, as observed in field studies across North American grasslands.^[71] Co-occurrence of these species peaks in agricultural grasslands, where limited patch sizes may exacerbate competition for suitable nesting substrates, though direct displacement events require further quantification.^[72] Grazing by domesticated cattle (Bos taurus) alters grassland vegetation height and density, indirectly shaping bobolink habitat use. In rotationally grazed systems, light spring grazing (late May to early June) followed by deferral until mid-July permits taller grass growth conducive to nesting, yielding higher fledging rates than in fields grazed before July 1; observational data from Ontario beef farms show paddocks ungrazed during peak breeding support densities up to 0.5 pairs per hectare.^[73] Conversely, intensive early-season grazing reduces cover, limiting site availability and correlating with lower abundance in mixed-grass prairies.^[39] Invasive cool-season grasses, including Kentucky bluegrass (Poa pratensis) and smooth brome (Bromus inermis), degrade bobolink habitats by dominating native warm-season flora, which diminishes forb diversity and litter accumulation critical for insect foraging and concealment. Northern prairie surveys report grassland bird densities, including bobolinks, declining by 20-50% in invaded stands due to homogenized structure, with management trials confirming restoration via invasive removal boosts occupancy.^[74]

Population Dynamics

Historical and Current Trends

The Bobolink population attained peaks prior to the 1960s, recovering from 19th-century reductions due to market hunting, before entering a period of sustained decline thereafter.^[75] North American Breeding Bird Survey (BBS) analyses document a cumulative reduction exceeding 50% since the mid-20th century, with losses reaching 65% between 1966 and 2015 in some assessments.^[57] ^[76] BBS data from 1966 to 2023 reveal an average annual decline of 1.7%, though rates vary regionally with steeper drops—approaching 10% per year—in core Midwest breeding areas such as Illinois and Indiana, compared to 2-3% in northeastern regions like Ontario and the eastern U.S.^[57] ^[77] ^[78] The 2025 U.S. State of the Birds report designates the Bobolink an "Orange Alert" tipping point species, reflecting halved populations over the past half-century alongside persistent downward trajectories validated by BBS metrics and Partners in Flight estimates of a current global breeding population near 10 million individuals.^[1] ^[57]

Demographic Factors

Adult apparent survival rates for Bobolinks average approximately 0.70, as estimated from mark-recapture data across multiple North American sites between 1992 and 2006.^[79] This high adult survival contrasts with low juvenile recruitment, reflected in post-fledging productivity estimates of 0.066–0.109 young per adult, indicating substantial mortality or dispersal challenges for first-year birds.^[79] Fecundity is closely linked to nest success, which varies widely from 6% to 44% depending on predation pressure and habitat conditions, with daily survival rates declining seasonally from 0.98 to 0.92 over the nesting period.^[80] ^[81] Bobolinks typically reach breeding age in their first full year, enabling rapid population turnover under stable conditions, though ongoing declines have shifted age structures toward older cohorts due to persistent low juvenile survival.^[80] Overall adult sex ratios approximate 1:1 parity, consistent with near-even nestling sex ratios of 1.03:1 observed across study sites, despite polygynous mating where males defend territories and court multiple females. ^[82] However, territorial displays during breeding exhibit male bias, as vocalizing and flight-song males are more conspicuous than females, who focus on nesting.^[83] Population regulation shows density dependence in breeding areas, with mark-recapture modeling revealing negative feedbacks on adult survival and post-breeding productivity as densities increase, alongside territory saturation that limits colony expansion in high-quality grasslands.^[79] ^[84] These dynamics, derived from integrated demographic models, underscore how intrinsic vital rates constrain recovery even absent external pressures.^[79]

Conservation

Threats from Habitat and Agriculture

The primary threats to Bobolinks from breeding habitats stem from the conversion of grasslands to urban development and afforestation of abandoned farmlands, which have reduced available nesting areas across their northern range.^[85] In agricultural landscapes, where Bobolinks preferentially nest in hayfields and meadows, early-season mowing—often timed to multiple cuts for higher yields—directly destroys nests and fledglings, with studies documenting that 100% of nests containing eggs or young nestlings affected by mowing in New York were abandoned or destroyed.^[86] Mowing has been identified as the cause of 51% of nest losses in monitored New York hayfields, as it severs the tall grasses required for concealment and coincides with peak nesting from late May through June, when young birds are flightless and vulnerable.^[39] These practices, driven by economic demands for livestock forage, prioritize crop productivity over wildlife timing, creating a causal tension between agricultural efficiency and grassland bird reproduction. Pesticide applications in breeding and wintering habitats further imperil Bobolinks by diminishing invertebrate prey, which constitutes the bulk of their diet during nesting and migration.^[17] Neonicotinoid insecticides, widely used on crops adjacent to grasslands, persist in soils and reduce insect populations essential for provisioning nestlings, with grassland species like Bobolinks showing heightened sensitivity due to their ground-foraging behavior.^[87] On wintering grounds in South America, where Bobolinks forage extensively in rice fields for seeds, farmers apply pesticides and rodenticides that poison foraging flocks, compounding indirect effects from prey depletion.^[88] Direct mortality occurs in southern rice paddies, where large Bobolink flocks are targeted as pests for consuming uneaten grains post-harvest, leading to intentional poisoning, shooting, and historical trapping for pets or food in countries like Argentina and Jamaica.^[57] ^[88] This persecution reflects a pragmatic agricultural response to crop losses—Bobolinks can consume significant rice volumes in flocks—but ignores the birds' role in controlling insect pests during off-seasons, highlighting trade-offs between short-term yield protection and long-term ecosystem services.^[89] Climate-driven phenological shifts exacerbate these agricultural conflicts, as warmer springs advance hay growth and mowing schedules while Bobolink arrival and nesting remain relatively stable, increasing nest destruction rates in mismatched timing.^[7] Long-term monitoring indicates that such mismatches, observed in New England hayfields, stem from decoupled responses—farmers adapt to earlier green-up for economic reasons, but avian cues tied to photoperiod delay breeding, resulting in greater overlap with harvest operations.^[90] This dynamic underscores how incremental climate effects amplify habitat pressures without altering fundamental agricultural imperatives for timely forage production.

Conservation Measures

One primary conservation strategy involves delayed hayfield mowing to allow completion of the bobolink breeding cycle, typically postponing cuts until after July 15 or August 1 in non-forage-dependent fields.^[91]^[92] Programs such as the Bobolink Project, administered by Mass Audubon in partnership with Audubon chapters across multiple states, provide financial incentives to farmers for modifying mowing schedules on enrolled grasslands, with applications for the 2025 season drawing participation from fields in at least four states.^[93]^[94] Empirical studies demonstrate that such delays increase nest survival rates and fledgling success, with one analysis of managed fields showing higher daily nest survival in areas avoiding mid-season mowing compared to early-cut sites.^[95]^[39] Grassland restoration and habitat incentives, including conservation easements and enrollment in programs like the U.S. Conservation Reserve Program (CRP), aim to maintain large patches of suitable nesting habitat exceeding 10-30 hectares.^[40]^[43] These efforts have been linked to stabilized local populations, as CRP conversions back to cropland could reduce bobolink numbers by approximately 10% in regions like North Dakota.^[23] Pesticide reduction initiatives, particularly integrated pest management in breeding and wintering agricultural areas, address direct mortality risks, with recommendations emphasizing minimized chemical inputs to protect foraging birds.^[96] International conservation in winter ranges, spanning southern South America, focuses on habitat protection in rice fields and pampas grasslands through awareness campaigns and reduced hunting under agreements like the Convention on Migratory Species.^[40]^[35] Population monitoring via the North American Breeding Bird Survey (BBS), operational since 1966, tracks trends through standardized roadside counts, supplemented by targeted transect and point-count surveys for breeding evidence in managed fields.^[97]^[98] These metrics have documented localized improvements, such as higher bobolink abundance in stewardship-monitored sites with delayed management.^[99]

Debates and Economic Trade-offs

Delayed haying practices to protect bobolink nests impose economic burdens on farmers, as cutting after mid-July results in lower-quality forage with reduced nutritional value and yield, necessitating purchases of replacement hay at additional cost.^[100] Compensation programs, such as those offering approximately $50 per acre, aim to offset these losses but cover only a fraction of potential revenue forgone from optimal timing, leading to debates over the viability of subsidizing bird habitat at the expense of agricultural productivity.^[7] Farmers argue that such delays exacerbate financial pressures in an industry already facing volatile markets and input costs, prioritizing food production over species-specific conservation where habitat overlaps with prime cropland.^[101] In South American wintering grounds, bobolinks are regarded as agricultural pests in rice fields, consuming seeds and prompting control measures including shooting, firecrackers, and occasional poisoning, which farmers justify as necessary to safeguard yields in staple crop regions.^[102] Interviews with Bolivian and Argentine producers highlight perceptions of bobolinks as "rice birds" warranting active deterrence, with limited data on actual crop damage but widespread implementation of scare tactics during late winter flocking.^[103] These interventions underscore trade-offs where bird protection could undermine rice production critical for regional food security, contrasting with northern conservation efforts and raising questions about equitable global burden-sharing. Conservation initiatives, including delayed mowing and grassland set-asides, have slowed but failed to reverse bobolink population declines, with long-term trends showing continued losses despite targeted programs like the Conservation Reserve Program.^[39] Empirical analyses indicate that breeding-season habitat interventions overlook migration and wintering bottlenecks, such as pesticide exposure, while historical data reveal that agricultural expansion in the 19th century initially expanded bobolink range by creating vast hayfields, suggesting intensification rather than farming per se as the primary driver of recent habitat loss.^[31] Critics contend that opportunity costs of land retirement for birds divert resources from human needs, with efficacy limited by scale—enrolling only thousands of acres amid millions converted to row crops—prioritizing comprehensive life-cycle threats over localized mowing debates.^[40]^[104]

References

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The species name of the Bobolink, oryzivorus means “rice eating” and refers to this bird's appetite for rice and other grains, especially during migration and ...Bobolink Range Map · Bobolink Sounds · Bobolink Identification · Life History
[2]
Bobolink Identification, All About Birds, Cornell Lab of Ornithology
Breeding male Bobolinks are mostly black with a white back and rump, and a rich buffy nape. Females and nonbreeding males are warm buffy brown, streaked with ...Missing: structure | Show results with:structure
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Bobolink | Audubon Field Guide
The male is unmistakable in spring finery, but before fall migration he molts into a striped brown appearance like that of the female.Missing: facts | Show results with:facts
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Bobolinks travel 12,500 miles round-trip from northern breeding grounds through Florida and the Gulf of Mexico to South America for wintering.Missing: Dolichonyx oryzivorus
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Listen to the Bubbly Jangling of a Bobolink's Song | Audubon
Apr 30, 2018 · Their nasal tissues contain minute quantities of the mineral magnetite, providing the birds a kind of built-in compass. Farmers who delay mowing ...
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Vermont Hay Season Is Shifting Earlier, But Nesting Birds Are ...
Nov 1, 2021 · Bobolinks winter in South America, centrally in Bolivia, Paraguay, and Argentina; most Savannah Sparrows winter in the southern United States ...
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How Farmers In New England Make Hay for Bobolinks | Audubon
Among the longest-migrating songbirds in the Western Hemisphere, Bobolinks travel from wintering grounds as far south as Argentina's rice fields and nest in ...
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Bobolink (Dolichonyx oryzivorus) | U.S. Fish & Wildlife Service
Scientific Name: Dolichonyx oryzivorus. Common Name: Bobolink. FWS Category: Birds. Kingdom: Animalia. Location in Taxonomic Tree. Genus: Dolichonyx.Missing: classification | Show results with:classification
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Dolichonyx oryzivorus (Bobolink) | PHILATAX
The genus name Dolichonyx is from Ancient Greek dolikhos, "long", and onux, "claw". The specific oryzivorus is from Latin oryza, "rice", and vorare, "to devour" ...
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Dolichonyx oryzivorus (Bobolink) - Avibase
The bobolink is a small New World blackbird and the only member of the genus Dolichonyx. An old name for this species is the rice bird.
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[12]
[PDF] A comprehensive species-level molecular phylogeny of the New ...
Dec 2, 2013 · Table 1. Taxa, specimens, and GenBank sequences used in phylogenetic analyses of New World blackbirds (Icteridae).
[13]
Losses of female song with changes from tropical to temperate ...
We determined relationships among our 65 taxa using a molecular phylogeny for the entire family Icteridae (Lanyon & Barker 2007). This phylogeny is based on ...Missing: position | Show results with:position
[14]
[PDF] Phylogeny and Behavioral Evolution in the Family Icteridae
In this review I discuss three additional icterid species, endemic to Brazil and Colombia, and not found in the molecular trees. RESULTS AND DISCUSSION. The DNA ...
[15]
Bobolink - Etymology, Origin & Meaning
1776, "the golden oriole," a bird of Europe, so called from its rich yellow color, from French oriol, Old Provençal auriol, from Medieval Latin oryolus, oriolus ...
[16]
bobolink, n. meanings, etymology and more
The earliest known use of the noun bobolink is in the late 1700s. OED's earliest evidence for bobolink is from 1774, in a diary entry by John Adams ...Missing: etymonline | Show results with:etymonline
[17]
Bobolink - American Bird Conservancy
The Bobolink's species name oryzivorus means “rice-eating” and refers to this bird's penchant for grains, particularly during migration and on its wintering ...Missing: etymology | Show results with:etymology
[18]
https://birdsoftheworld.org/bow/species/boboli/1.0/introduction
[19]
(species) dolichonyx oryzivorus - WY Field Guide
Adults weigh roughly 43 g (males average larger than females), range in length from 15.2–20.5 cm, and have a wingspan of about 29.2 cm (Sibley 2003; Renfrew et ...
[20]
Plumages, Molts, and Structure - Bobolink - Dolichonyx oryzivorus
Bobolinks have 9 functional primaries, 9 secondaries (including 3 tertials), and 12 rectrices. Little or no geographic variation in appearance.Missing: morphology | Show results with:morphology
[21]
[PDF] Bobolink (Dolichonyx Oryzivorus) - DUNE
Aug 13, 2015 · Results from birds tagged with geolocators show that Bobolinks strain our traditional notion of a stationary non-breeding range, as birds make ...
[22]
Flapping before Flight: High Resolution, Three-Dimensional Skeletal ...
Apr 21, 2016 · Flight-capable adult birds have many morphological features that are presumably adaptations or exaptations for meeting aerial challenges.Fig 1. Ontogeny Of Flight... · Fig 3. Ontogenetic Trends... · Role Of The Hind Limbs
[23]
Bobolink | North Dakota Game and Fish
L 7”, WS 11.5”, 1.5 oz. Males sport a black belly, white rump and back, white patch on wings, and yellow hind neck. The female is yellowish-buff overall.Missing: plumage sexual
[24]
[PDF] Where the Boys Are
Feb 2, 2020 · The adult male Bobolink in breeding plumage (left) is so different from non-breeding adults of either sex (right) that the bird was reckoned two.Missing: eclipse | Show results with:eclipse
[25]
[PDF] Bobolink (Dolichonyx oryzivorus) - Species at risk public registry
COSEWIC assessment and status report on the Bobolink Dolichonyx oryzivorus in ... The species is considered secure according to the IUCN. Red List (NatureServe, ...
[26]
Dolichonyx oryzivorus (bobolink) - Animal Diversity Web
Currently, bobolinks have a conservation status of 'least concern' according to the IUCN Red List of Threatened Species. This has changed over the past 100 ...
[27]
Distribution - Bobolink - Dolichonyx oryzivorus - Birds of the World
Isolated breeding populations are found in central Washington, ne. Nevada, n. Utah, e. Arizona, Kansas, n.-central Kentucky (American Ornithologists' Union 1983 ...
[28]
Bobolink (Dolichonyx oryzivorus): COSEWIC assessment and status ...
Apr 11, 2023 · Fire and fire suppression (IUCN 7.1) – fire control on both the breeding and wintering grounds allowing forest succession to replace grassland ...
[29]
Dolichonyx oryzivorus - Bobolink - NatureServe Explorer
Dolichonyx oryzivorus (Linnaeus, 1758) (TSN 179032). Conservation Status. NatureServe Status. Global Status: G5. Global Status Last Reviewed: 4/7/2016. Rank ...
[30]
Bobolink - Minnesota Breeding Bird Atlas
Data gathered by the federal Breeding Bird Survey (BBS) have helped biologists estimate the North American population of Bobolinks at 9.7 million breeding ...
[31]
[PDF] Bobolink Species Status Assessment - NY.Gov
Jan 12, 2024 · Details of historic and current occurrence: The first Breeding Bird Atlas (BBA) (1980-85) documented occupancy in 3,465 blocks, 65% of the.
[32]
The Bobolink Project - Green Mountain Audubon Society
Jul 9, 2018 · By one estimate half of the Bobolink population has disappeared since 1970. In Vermont the most recent Breeding Bird Atlas recorded a modest 6% ...
[33]
[PDF] Dolichonyx oryzivorus (Bobolink) - UWI St. Augustine
APPLIED ECOLOGY. Dolichonyx oryzivorus is listed under the IUCN as a species of Least Concern. This status is justified by the rate of decline of the species ...<|control11|><|separator|>
[34]
Bobolink - Wildlife in Winter
Feb 10, 2022 · Bobolinks are neotropical migrants and will travel by night more than 5000 miles to the pampas region of southwestern Brazil, Paraguay, and Argentina.
[35]
[PDF] Status and Conservation of the Bobolink (Dolichonyx oryzivorus) in ...
For example, Martin and Gavin (1995) indicated that during the non-breeding season Bobolinks are found in. "pampas" (southern temperate grasslands) of South.
[36]
[PDF] On the Winter Distribution of the Bobolink (dolichonyx Oryzivorus ...
Sep 6, 2024 · of the Amazon, until it reaches what may be its true winter quar- ters in southern or southwestern Brazil. Proceeding with our records, we ...
[37]
[PDF] Nonbreeding season movements of a migratory songbird are related ...
May 6, 2019 · For example, Bobolinks originating from 3 different breeding populations all made synchronized nonbreeding movements as they tracked re- sources ...
[38]
Phenological matching across hemispheres in a long‐distance ...
Mar 11, 2013 · During the non-breeding season, Bobolinks may change their roost location during the day (Renfrew & Saavedra, 2007); we used only midnight ...
[39]
[PDF] The Effects of Management Practices on Grassland Birds—Bobolink ...
Keys to Bobolink (Dolichonyx oryzivorus) management are providing large areas of suitable habitat (for example, native or tame grasslands of moderate vegetative ...
[40]
[PDF] A Full Life Cycle Conservation Plan for Bobolink
On the winter distribution of the bobolink (Dolichonyx oryzivorus) with remarks on ... (Dolichonyx oryzivorus) in Argentina in C.J. Ralph, and T.D. Rich, editors.
[41]
Movements and Migration - Bobolink - Dolichonyx oryzivorus
Populations across the breeding range generally converge and mix on the migration and overwintering grounds, and exhibit no coarse-scale migratory connectivity.
[42]
Bobolink - Conserve Wildlife Foundation of NJ
In late June and early July, post-breeding bobolinks concentrate in freshwater and coastal marshes where they remain for several weeks to molt. From early ...
[43]
Bobolink - Wisconsin All-Bird Conservation Plan
Restoration efforts meant to increase nesting habitat for this species should be evaluated to better inform future efforts. ... Bobolink (Dolichonyx oryzivorus).
[44]
[PDF] Migration Tactics Of A Long-Distance Migratory Songbird ... - DUNE
We compare migration timing among 4 populations of Bobolink (Dolichonyx oryzivorus) from across the breeding range using data from light-level geolocators.
[45]
[PDF] Bioenergetics of Lipid Deposition in the Bobolink, a Trans-equatorial ...
Migration places severe demands on the energy balance of a bird, especially if long distances are to be flown. Ability to store and utilize fat rapidly, ...Missing: endurance | Show results with:endurance
[46]
Winter diet of Bobolink, a long-distance migratory grassland bird ...
Jun 21, 2017 · Non-breeding season habitat quality mediates the strength of density-dependence for a migratory bird. Proceedings of the Royal Society B 282 ...
[47]
Prevalent transoceanic fall migration by a 30-gram songbird, the ...
Aug 7, 2025 · From 2013 to 2017, I used geolocators to study variation in the fall migratory track of the Bobolink (Dolichonyx oryzivorus) from a population ...
[48]
[PDF] Bobolink Migratory Pathways and Their Experimental Analysis ...
Sep 5, 2024 · In spring the edge of the passage advances slowly; in fall the initial movement may be extensive. An excellent example of this unseen fall ...
[49]
Migratory birds – BirdsCaribbean
Some take inland routes through Mexico and Central America, while others cross the Gulf of Mexico to overwinter on islands like Cuba, Jamaica, Hispaniola, and ...
[50]
Breeding - Bobolink - Dolichonyx oryzivorus - Birds of the World
Older males generally precede yearlings by several days. Females normally begin arriving 4–8 days after initial group of territorial males.
[51]
[PDF] The Breeding Biology of an Isolated Bobolink Population in Oregon
Oct 1, 1978 · Spring arrival dates were determined from surveys conducted in early May. I visited the principal study area daily beginning on 7 May each year.
[52]
Patterns of Extra-Pair Fertilizations in Bobolinks - jstor
Females are generally single- brooded (Gavin 1984). We studied bobolinks during the 1983-1986 breeding seasons at 10 sites in west central New York (Table 1).
[53]
Variation in Surrogate Breeding Habitat Quality Between ...
Bobolink abundance and daily survival rate (DSR) of nests were modeled ... Nesting success was highest in hayfields with taller vegetation, while in ...
[54]
[PDF] Responses of Nesting Bobolinks (Dolichonyx oryzivorus) to Habitat ...
Bobolinks (Dolichonyx oryzivorus) have con- sistently been reported to be area sensitive. (e.g. Herkert 1994, Bollinger 1995, Johnson and Igl 2001) and to avoid ...
[55]
Diet and Foraging - Bobolink - Dolichonyx oryzivorus
Stomach contents (n = 5) and fecal analysis indicate insects eaten while feeding in rice, and only insects consumed in soybean fields (Renfrew 2007, RBR).Missing: composition | Show results with:composition
[56]
Bobolink (Dolichonyx oryzivorus): COSEWIC assessment and status ...
Feb 23, 2018 · The Bobolink is a medium-sized passerine (total length: 16.5 - 20.2 cm ; Godfrey, 1986) with a body mass ranging from 33.9 ± 2.1 g (n = 142 ...
[57]
Bobolink Life History, All About Birds, Cornell Lab of Ornithology
Perched on a grass stem or displaying in flight over a field, breeding male Bobolinks are striking. No other North American bird has a white back and black ...
[58]
Diet of the Bobolink (Dolichonyx oryzivorus) in rice fields on its ...
Dec 30, 2019 · We confirmed that the Bobolink's diet in this region during this period is predominantly herbivorous (97%) and rice-based (55%), although it ...
[59]
(PDF) Ecology and conservation of Bobolinks (Dolichonyx ...
Aug 7, 2025 · Bobolinks showed a preference for the Grano de Oro variety of rice, and fed on rice only in the "masoso" or soft stage of seed formation, 10-14 ...
[60]
Bobolink Sounds, All About Birds, Cornell Lab of Ornithology
Bobolinks use a pink sound all year round to communicate within flocks, and they have several additional calls during the breeding season.Missing: Dolichonyx oryzivorus
[61]
Tests of the Function of the Song Repertoire in Bobolinks - jstor
Bobolinks (Dolichonyx oryzivorus) have a two song repertoire consisting of an alpha song and a beta song. The alpha song consists of distinct introductory notes ...
[62]
[PDF] Song Dialects in the Bobolink (dolichonyx Oryzivorus)
Jan 1, 1977 · We heard essentially no singing by male. Bobolinks in the Lake Itasca region after the hatching of eggs in late June and early July. Thus, it ...Missing: calls | Show results with:calls
[63]
The Bobolink (Dolichonyx oryzivorus)-Song |
May 3, 2018 · Sound spectrogram of male Bobolink song from Chase Lake in Minnesota. See how different it is from the Oregon Bobolink from above! Taken ...Missing: calls properties
[64]
[PDF] American Bittern depredation of Bobolink and Meadowlark nests
Other occasional predators include snakes, and birds such as Brown- headed Cowbirds (Molothrus ater),. Northern Harriers (Circus cyaneus),. Buteo spp. and if ...
[65]
Bobolink (Dolichonyx oryzivorus): recovery strategy [proposed] 2022
Aug 9, 2022 · Bobolinks are generally absent from woodland, shrubland and row crops, only occasionally nest in small-grain fields and avoid areas with high ...
[66]
Bobolink Bird Facts (Dolichonyx oryzivorus) | Birdfact
Bobolinks face threats from various predators, including hawks, owls, foxes, and snakes, which prey on adults, nestlings, and eggs. Did You Know? Bobolinks ...
[67]
How To Use Camera Traps - Adirondack Watershed Institute
Dec 14, 2023 · Additionally, camera traps are employed innovatively to identify predators of bird nests, including those of grassland species like bobolink ...
[68]
Haemosporidian parasite community in migrating bobolinks on the ...
Avian haemosporidian parasites are a highly diverse group of dipteran-borne blood parasites. Plasmodium, Haemoproteus and Leucocytozoon being the most common ...
[69]
Local parasite lineage sharing in temperate grassland birds ...
Jan 11, 2016 · Homologous DNA sequences from parasites detected in bobolinks and more sedentary birds (e.g., brown‐headed cowbirds Molothrus ater, and other co ...
[70]
Multiple lineages of Avian malaria parasites (Plasmodium) in the ...
Two of the ephemeral Plasmodium lineages (B and C) found in Galapagos birds matched parasite sequences from Bobolinks. Although this is not confirmation that ...
[71]
Heterospecific competition and attraction in grassland bird ...
Dec 30, 2015 · ... (Dolichonyx oryzivorus), Eastern Meadowlark (Sturnella magna), Field ... We found grassland bird assemblages are structured by interspecific ...
[72]
[PDF] Studies of Bobolink and Related Bird Habitats on Agricultural Lands ...
The main goal of the studies in Norfolk County was to gain a greater understanding of the extent to which grassland species of breeding birds, and in particular ...
[73]
Rotational grazing of beef cattle to support Bobolink breeding success
Our results illustrate that paddocks on rotationally grazed beef cattle farms that are ungrazed until the Bobolink breeding season is finished or grazed lightly ...
[74]
Impacts and management of invasive cool‐season grasses in the ...
Aug 17, 2013 · Invasive cool-season grasses can decrease the structural composition in prairies by outcompeting native plant species and reducing species ...
[75]
Bobolink Species account - Bird Population Studies
BBS data indicate that Bobolink populations have generally declined throughout their breeding range (Trend Map). Areas with increasing populations tend to be ...
[76]
Bobolinks have lost over 65% of their population since 1966, largely ...
Jul 23, 2025 · Bobolinks have lost over 65% of their population since 1966, largely due to habitat loss. As grassland birds, their breeding areas are often ...
[77]
ON GRASSLAND BIRD CONSERVATION IN THE NORTHEAST
A case in point is the Bobolink, which is declining at rates approaching 10% per year in Illinois and Indiana (Herkert 1997, Wells and Rosenberg 1999). In the ...
[78]
Bobolink Evaluation | ontario.ca
Aug 8, 2017 · Breeding Bird Survey ( BBS ) data for 1966-2007 indicate a significant decline averaging 1.8 percent per year, which amounts to a 53% decline ...
[79]
Bobolink (Dolichonyx oryzivorus)
These results suggest that the overall index of population density for Bobolink was high, about 45% higher than the mean index for all sparrow (Emberizidae) ...<|separator|>
[80]
Demography and Populations - Bobolink - Dolichonyx oryzivorus
Grazing. In rotationally grazed systems in Vermont, predation and trampling by cows accounted for 32% of nest failures. Both nest success (6–44%) and annual ...
[81]
Diverse demographic factors influence apparent juvenile survival in ...
Oct 27, 2021 · These survival estimates between fields are consistent with research indicating that reproductive success in Bobolinks is greater on fields ...Missing: fecundity | Show results with:fecundity
[82]
[PDF] POLYGYNY, MALE PARENTAL CARE, AND SEX RATIO IN SONG ...
Breeding within the population was asynchronous because of an experiment on the southeastern half of the island reported elsewhere (Smith et al. 1980). One ...<|separator|>
[83]
Behavior - Bobolink - Dolichonyx oryzivorus - Birds of the World
On overwintering grounds, foraging and roosting flocks are typically very vocal, and respond to arrival of a raptor by simultaneously ceasing all vocalizations.Behavior · Self-Maintenance · Locomotion
[84]
Vegetation Structure, Food Supply, and Polygyny in Bobolinks ... - jstor
Key words: Bobolinks; Dolichonyx oryzivorus; food resources; nest success; polygyny; territory ... The territory and its density dependent effect in Spiza ...
[85]
Bobolink - Audubon North Carolina
Now, with much abandoned farmland converting to forest and increasing development of their habitats, the Bobolink population has seen a dramatic decline.
[86]
[PDF] Species Assessment for Bobolink - NY.Gov
Breeding Bird Survey data for New York show a significant annual decline of 0.8% ... Bobolink (Dolichonyx oryzivorus), The Birds of North. America Online (A.
[87]
Playing the Long Game to Reduce Pesticide Threats
Apr 4, 2024 · Grassland birds like the Bobolink and the Endangered Attwater's Prairie-Chicken are especially threatened. Neonics were designed to be highly ...
[88]
Bird of the Month: Bobolink - NH Audubon
May 15, 2023 · Mowing is by far the greatest threat to Bobolink populations in the Northeast: it destroys nests outright and exposes undamaged ones to ...Missing: foxes | Show results with:foxes
[89]
Winter diet of Bobolink, a long-distance migratory grassland bird ...
Jun 21, 2017 · Large flocks of wintering Bobolinks are regularly observed feeding in South American rice fields (Blanco et al. 2006, Renfrew and Saavedra ...
[90]
Agriculture is adapting to phenological shifts caused by climate ...
May 18, 2021 · Savannah Sparrows (Passerculus sandwichensis) and Bobolinks (Dolichonyx oryzivorus) are ground-nesting grassland songbirds that use ...
[91]
The Bobolink Project | Audubon Vermont
Conserving Bobolink habitat will help other declining grassland bird species such as Eastern Meadowlark and Grasshopper Sparrow.
[92]
Waiting to mow helps preserve the bobolink - Farm and Dairy
Jun 18, 2020 · Farmers delay mowing at least some hay fields until after July 15 to save bobolinks and other grassland birds that nest in them.Missing: measures | Show results with:measures
[93]
The Bobolink Project
The Bobolink Project uses donated funds to provide financial assistance to participating farmers who modify their mowing schedules so that grassland nesting ...Missing: afforestation | Show results with:afforestation
[94]
The Bobolink Project Takes Flight: Applications Now Open
Nov 25, 2024 · The Bobolink Project supports grassland birds by partnering with farmers to manage habitats and address extinction threats from habitat ...<|separator|>
[95]
[PDF] Impact of Delayed Mowing on Restoring Populations of Grassland ...
Delaying mowing until after the nesting season likely increases overall survival and reproductive success of grassland birds on these fields. Although we ...
[96]
Bobolink Dolichonyx oryzivorus population decline in agricultural ...
A bobolink population decline of over 90% between 1966 and 1992, a decline that was significantly correlated with documented declines in the regional area of ...
[97]
North American Breeding Bird Survey
The North American Breeding Bird Survey (BBS) was formally launched in 1966 when approximately 600 surveys were conducted in the US and Canada east of the ...
[98]
Monitoring Bobolink stewardship – BECO
We assessed the efficacy of low-intensity field surveys (ie, transect surveys, point counts) to estimate Bobolink abundance and detect evidence of breeding.
[99]
[PDF] Monitoring bobolink abundance and breeding in response to ...
The purpose of this monitoring scheme is to assess the abundance and fledging success of bobolink in fields (e.g., hay field, pasture, restored grassland) ...
[100]
Is Hay for the Birds? Investigating Landowner Willingness to Time ...
One promising strategy to protect grassland and farmland breeding birds is to avoid harvesting hay during the main bird breeding season, and delay hay harvest ...
[101]
Wildlife Habitat Protected In First Test Of Ecological Investment ...
Jun 29, 2007 · By compensating the farmers for the cost of delaying the harvest and purchasing replacement hay, the birds have enough time to mature and ...
[102]
Conservation and Management - Bobolink - Dolichonyx oryzivorus
Conservation Status Protected under Migratory Bird Treaty Act. Listed as threatened in one state and one province, a Species of Special Concern in eight states ...
[103]
[PDF] Ecology and Conservation of Bobolinks (dolichonyx Oryzivorus) in ...
When appropriate, foraging sub- strate (plant or insect species) was recorded. Bobolink flocks were monitored with 7–10X binoculars or scope (20x) to obtain a ...Missing: techniques | Show results with:techniques
[104]
The Life History and Conservation of Bobolinks
May 19, 2020 · Long-term surveys have documented similar declines for other grassland birds of our region, including Upland Sandpipers, Short-eared Owls, Sedge ...