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ABSTRACT Band-recovery and wing-collection survey data have the potential to provide information on American woodcock (Scolopax minor) fall migration ecology in the Central Region of the United States, yet researchers have not recently analyzed these extensive data sets. We analyzed all direct recoveries of woodcock banded in Michigan, Minnesota, and Wisconsin, USA, as well as wing-collection survey data, to determine the progression of fall migration, the migration direction, and the final destination of woodcock migrating from these states. We did not observe migration initiation based on band recoveries until late October and early November, with most migration occurring during November. Wing-receipt data showed a similar trend, with most change in mean receipt latitude occurring from 1 November to 5 December. During November, wing receipts were spread through the entire Central Region. By 15–31 December, 92% (n = 26) of band recoveries were on the wintering grounds (south of latitude 33°N). Most banded woodcock from Michigan, Minnesota, and Wisconsin wintered in Louisiana, USA. Woodcock banded in these states will be exposed to harvest for most of the hunting season because they remain in these states through November. If the population status of local birds is a concern, managers should consider this migration pattern when setting season dates. 相似文献
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Emily B. Blackman Christopher S. Deperno Ron W. Heiniger Matthew J. Krachey Christopher E. Moorman M. Nils Peterson 《The Journal of wildlife management》2012,76(3):528-533
Since the late 1960s, American woodcock (Scolopax minor) have undergone population declines because of habitat loss. Previous research suggested ridge and furrow topography in conventionally tilled soybean fields provided critical nocturnal cover as birds foraged on earthworms. However, the use of no-till technology has increased and many fields now lack ridge and furrow topography. We assessed woodcock winter nocturnal foraging habitat use given recent changes in agricultural technology, and investigated how field treatment, earthworm abundance, and environmental variables affect the selection of nocturnal foraging sites. We counted woodcock along transects in 5 field treatments twice in each of 67 fields during December–March 2008–2009 and 72 fields during December–March 2009–2010. During both seasons, we collected earthworm and soil samples from a subset of fields of each field treatment. Woodcock densities were at least twice as high in no-till soybean fields planted after corn and in undisked corn fields with mowed stalks than in other field treatments. No-till soybean planted after corn and undisked corn fields contained ridge and furrow topography, whereas other crops did not, and earthworms were at least 1.5 times more abundant in no-till soybean fields than other field treatments. Ridges and furrows in no-till soybean fields planted after corn and undisked corn fields may provide wintering woodcock with thermal protection and concealment from predators. No-till soybean fields planted after corn offered the additional benefit of relatively high food availability. The presence of ridge and furrow topography can be used to predict woodcock field use on the wintering grounds in agricultural areas. Farmers can provide nocturnal winter foraging sites for woodcock by delaying field disking and leaving ridge and furrow topography in crop fields. © 2011 The Wildlife Society. 相似文献
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JED MEUNIER RUI SONG R. SCOTT LUTZ DAVID E. ANDERSEN KEVIN E. DOHERTY JOHN G. BRUGGINK EILEEN OPPELT 《The Journal of wildlife management》2008,72(2):440-448
ABSTRACT Investigation of bird migration has often highlighted the importance of external factors in determining timing of migration. However, little distinction has been made between short- and long-distance migrants and between local and flight birds (passage migrants) in describing migration chronology. In addition, measures of food abundance as a proximate factor influencing timing of migration are lacking in studies of migration chronology. To address the relationship between environmental variables and timing of migration, we quantified the relative importance of proximate external factors on migration chronology of local American woodcock (Scolopax minor), a short distance migrant, using event-time analysis methods (survival analysis). We captured 1,094 woodcock local to our study sites in Michigan, Minnesota, and Wisconsin (USA) during autumn 2002–2004 and documented 786 departure dates for these birds. Photoperiod appeared to provide an initial proximate cue for timing of departure. Moon phase was important in modifying timing of departure, which may serve as a navigational aid in piloting and possibly orientation. Local synoptic weather variables also contributed to timing of departure by changing the rate of departure from our study sites. We found no evidence that food availability influenced timing of woodcock departure. Our results suggest that woodcock use a conservative photoperiod-controlled strategy with proximate modifiers for timing of migration rather than relying on abundance of their primary food, earthworms. Managing harvest pressure on local birds by adjusting season lengths may be an effective management tool with consistent migration patterns from year to year based on photoperiod. 相似文献
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Joseph D. Moore David E. Andersen Thomas R. Cooper Jeffrey P. Duguay Shaun L. Oldenburger C. Al Stewart David G. Krementz 《The Journal of wildlife management》2019,83(7):1617-1627
American woodcock (Scolopax minor; woodcock) migratory connectivity (i.e., association between breeding and wintering areas) is largely unknown, even though current woodcock management is predicated on such associations. Woodcock are currently managed in the Eastern and Central management regions in the United States with the boundary between management regions analogous to the boundary between the Atlantic and Mississippi flyways, based largely on analysis of band returns from hunters. Factors during migration influence survival and fitness, and existing data derived from banding and very high frequency telemetry provide only coarse-scale information to assess factors influencing woodcock migratory movement patterns and behavior. To assess whether current management-region boundaries correspond with woodcock migratory connectivity in the Central Management Region and to describe migration patterns with higher resolution than has been previously possible, we deployed satellite transmitters on 73 woodcock (25 adult and 28 juvenile females, and 8 adult and 12 juvenile males) and recorded 87 autumn or spring migration paths from 2014 to 2016. Marked woodcock used 2 primary migrations routes: a Western Route and a Central Route. The Western Route ran north-south, connecting the breeding and wintering grounds within the Central Management Region. The hourglass-shaped Central Route connected an area on the wintering grounds reaching from Texas to Florida, to sites throughout northeastern North America in both the Eastern Management Region and Central Management Region and woodcock following this route migrated through the area between the Appalachian Mountains and the Mississippi Alluvial Valley in western Tennessee during autumn and spring. Two of 17 woodcock captured associated with breeding areas in Michigan, Wisconsin, or Minnesota migrated to wintering sites in the Eastern Management Region and 12 marked woodcock captured on wintering areas in Texas and Louisiana migrated to breeding sites in the Eastern Management Region. Woodcock that used the Western Route exhibited high concentrations of stopovers during spring in the Arkansas Ozark Mountains and northern Missouri, and along the Mississippi River on the border between Wisconsin and Minnesota, and autumn concentrations of stopovers in southwestern Iowa, central Missouri, the Arkansas portion of the Ozark Mountains, and around the junction of Texas, Louisiana, Oklahoma, and Arkansas. Woodcock that used the Central Route exhibited high concentrations of stopovers during spring in northern Mississippi through western Tennessee, western Kentucky, and the Missouri Bootheel, and autumn concentrations of stopovers in northern Illinois, southwestern Ohio, and the portions of Kentucky and Tennessee west of the Appalachian Mountains. We suggest that current management of woodcock based on 2 management regions may not be consistent with the apparent lack of strong migratory connectivity we observed. Our results also suggest where management of migration habitat might be most beneficial to woodcock. © 2019 The Wildlife Society. 相似文献
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Roger J. Masse Brian C. Tefft Scott R. Mcwilliams 《The Journal of wildlife management》2015,79(8):1378-1384
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JOHN R. SAUER WILLIAM A. LINK WILLIAM L. KENDALL JAMES R. KELLEY DANIEL K. NIVEN 《The Journal of wildlife management》2008,72(1):204-214
Abstract The Singing-Ground Survey (SGS) is a primary source of information on population change for American woodcock (Scolopax minor). We analyzed the SGS using a hierarchical log-linear model and compared the estimates of change and annual indices of abundance to a route regression analysis of SGS data. We also grouped SGS routes into Bird Conservation Regions (BCRs) and estimated population change and annual indices using BCRs within states and provinces as strata. Based on the hierarchical model–based estimates, we concluded that woodcock populations were declining in North America between 1968 and 2006 (trend = −0.9%/yr, 95% credible interval: −1.2, −0.5). Singing-Ground Survey results are generally similar between analytical approaches, but the hierarchical model has several important advantages over the route regression. Hierarchical models better accommodate changes in survey efficiency over time and space by treating strata, years, and observers as random effects in the context of a log-linear model, providing trend estimates that are derived directly from the annual indices. We also conducted a hierarchical model analysis of woodcock data from the Christmas Bird Count and the North American Breeding Bird Survey. All surveys showed general consistency in patterns of population change, but the SGS had the shortest credible intervals. We suggest that population management and conservation planning for woodcock involving interpretation of the SGS use estimates provided by the hierarchical model. 相似文献
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A detailed knowledge of the habitat requirements of steppe birds living in farmland habitats is necessary to identify agricultural practices compatible with their conservation. The globally threatened Great Bustard Otis tarda is a partial migrant in central Iberia, but factors affecting its winter habitat use have not been identified. We assessed habitat differences between breeding and wintering areas and winter habitat selection of radiotagged migrant female Great Bustards in central Spain. Of 68 tagged females, 35% moved to wintering areas located 64.3 ± 24.0 km south of their breeding areas, and 80% wintered in a single area of c. 236 km2. A census of the population in this area identified it as one of the most important wintering areas of this species in the world, holding c. 1500 individuals. There were significant differences between breeding and wintering habitats of individually marked migrant females. Compared with breeding areas, wintering areas of migrant females were located further from roads and urban nuclei, had lower human population densities and area of urban developments, and a higher diversity of land‐use types, with less cover of cereals and more vineyards and olive groves. Within this area, radiotracked migrant females preferred sites with more vineyards and a lower land‐use diversity. Our results highlight the importance of traditional Mediterranean dry farmland mosaics, and suggest that different conservation strategies are needed for migrant and resident populations in winter to secure the conservation of suitable wintering habitat for Great Bustards in the Iberian Peninsula. 相似文献
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Arzu Gürsoy-Ergen 《Zoology in the Middle East.》2019,65(2):116-127
The development of the breeding and non-breeding populations of the White-headed Duck, Oxyura leucocephala, in Turkey was analysed based on all available records from the period 1966–2016 from 99 different areas. Breeding is confined to Inner Anatolia and the eastern parts of the country. The breeding population had been estimated as 200–250 pairs in the period 1996–2001 but recent observations show that it does now not exceed 80–125 pairs which is a decline of about 50% within two decades. The non-breeding winter population comprises approximately 8,500–10,000 individuals. Burdur Lake has traditionally housed more than 90% of the population but is no longer a significant resting place. The numbers started to decrease from more than 10,000 birds at the beginning of the 1990s to a few hundred in the early 2000s. Now only very small numbers overwinter there. The reason seems to be a combination of water pollution and decreasing water level. After a period of more than 10 years, the numbers in Turkey started to increase again, and most birds are now concentrated at Manyas Lake in Western Anatolia. In 2016, the population reached a winter maximum of approximately 6,000. In the post-breeding season, up to 4,000 individuals were recorded in Eastern Anatolia in October 2014 which is far more than has ever been recorded in this season before. 相似文献
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Juliet A. Vickery Steven R. Ewing Ken W. Smith Deborah J. Pain Franz Bairlein Jana Škorpilová Richard D. Gregory 《Ibis》2014,156(1):1-22
There is compelling evidence that Afro‐Palaearctic (A‐P) migrant bird populations have declined in Europe in recent decades, often to a greater degree than resident or short‐distance migrants. There appear to have been two phases of decline. The first in the 1960s–1970s, and in some cases into the early 1980s, largely affected species wintering predominantly in the arid Sahelian zone, and the second since the 1980s has mostly affected species wintering in the humid tropics and Guinea forest zone. Potential drivers of these declines are diverse and are spread across and interact within the migratory cycle. Our knowledge of declining species is generally better for the breeding than the non‐breeding parts of their life cycles, but there are significant gaps in both for many species. On the breeding grounds, degradation of breeding habitats is the factor affecting the demography of the largest number of species, particularly within agricultural systems and woodland and forests. In the non‐breeding areas, the interacting factors of anthropogenic habitat degradation and climatic conditions, particularly drought in the Sahel zone, appear to be the most important factors. Based on our synthesis of existing information, we suggest four priorities for further research: (1) use of new and emerging tracking technologies to identify migratory pathways and strategies, understand migratory connectivity and enable field research to be targeted more effectively; (2) undertake detailed field studies in sub‐Saharan Africa and at staging sites, where we understand little about distribution patterns, habitat use and foraging ecology; (3) make better use of the wealth of data from the European breeding grounds to explore spatial and temporal patterns in demographic parameters and relate these to migratory pathways and large‐scale patterns of habitat change and climatic factors; and (4) make better use of remote sensing to improve our understanding of how and where land cover is changing across these extensive areas and how this impacts A‐P migrants. This research needs to inform and underpin a flyway approach to conservation, evaluating a suite of drivers across the migratory cycle and combining this with an understanding of land management practices that integrate the needs of birds and people in these areas. 相似文献
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The Mid-continent Population (MCP) of sandhill cranes (Grus canadensis) is widely hunted in North America and is separated into the Gulf Coast Subpopulation and Western Subpopulation for management purposes. Effective harvest management of the MCP requires detailed knowledge of breeding distribution of subspecies and subpopulations, chronology of their use of fall staging areas and wintering grounds, and exposure to and harvest from hunting. To address these information needs, we tagged 153 sandhill cranes with Platform Transmitting Terminals (PTTs) during 22 February–12 April 1998–2003 in the Central and North Platte River valleys of south-central Nebraska. We monitored PTT-tagged sandhill cranes, hereafter tagged cranes, from their arrival to departure from breeding grounds, during their fall migration, and throughout winter using the Argos satellite tracking system. The tracking effort yielded 74,041 useable locations over 49,350 tag days; median duration of tracking of individual cranes was 352 days and 73 cranes were tracked >12 months. Genetic sequencing of mitochondrial DNA (mtDNA) from blood samples taken from each of our random sample of tagged cranes indicated 64% were G. c. canadensis and 34% were Grus canadensis tabida. Tagged cranes during the breeding season settled in northern temperate, subarctic, and arctic North America (U.S. [23%, n = 35], Canada [57%, n = 87]) and arctic regions of northeast Asia (Russia [20%, n = 31]). Distribution of tagged cranes by breeding affiliation was as follows: Western Alaska–Siberia (WA–S, 42 ± 4% [SE]), northern Canada–Nunavut (NC–N, 21 ± 4%), west-central Canada–Alaska (WC–A, 23 ± 4%) and East-central Canada–Minnesota (EC–M, 14 ± 3%). All tagged cranes returned to the same breeding affiliation used during the previous year with a median distance of 1.60 km (range: 0.08–7.7 km, n = 53) separating sites used in year 1 and year 2. Fall staging occurred primarily in central and western Saskatchewan (69%), North Dakota (16%), southwestern Manitoba (10%), and northwestern Minnesota (3%). Space-use sharing indices showed that except for NC–N and WC–A birds, probability of finding a crane from one breeding affiliation within the home range of another breeding affiliation was low during fall staging. Tagged cranes from WC–A and EC–M breeding affiliations, on average, spent 25 and 20 days, respectively, longer on fall staging areas in the northern plains than did WA–S and NC–N birds. Cranes in the NC–N, WA–S, and WC–A affiliations spent 99%, 74%, and 64%, respectively, of winter in western Texas in Hunting Zone A; EC–M cranes spent 83% of winter along the Texas Gulf Coast in Hunting Zone C. Tagged cranes that settled within the breeding range of the Gulf Coast Subpopulation spent 28% and 42% of fall staging and winter within the range of the Western Subpopulation, indicating sufficient exchange of birds to potentially limit effectiveness of MCP harvest management. Harvests of EC–M and WC–A cranes during 1998–2003 were disproportionately high to their estimated numbers in the MCP, suggesting more conservative harvest strategies may be required for these subpopulations in the future, and for sandhill cranes to occupy major parts of their historical breeding range in the Prairie Pothole Region. Exceptionally high philopatry of MCP cranes of all 4 subpopulations to breeding sites coupled with strong linkages between crane breeding distribution, and fall staging areas and wintering grounds, provide managers guidance for targeting MCP crane harvest to meet management goals. Sufficient temporal or spatial separation exists among the 4 subpopulations on fall staging areas and wintering grounds to allow harvest to be targeted at the subpopulation level in all states and provinces (and most hunting zones within states and provinces) when conditions warrant. Knowledge gained from our study provides decision-makers in the United States, Canada, Mexico, and Russia with improved guidance for developing sound harvest regulations, focusing conservation efforts, and generating collaborative efforts among these nations on sandhill crane research and management to meet mutually important goals. © 2011 The Wildlife Society. 相似文献
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Veen T Svedin N Forsman JT Hjernquist MB Qvarnström A Hjernquist KA Träff J Klaassen M 《Proceedings. Biological sciences / The Royal Society》2007,274(1610):707-712
In the face of hybridization, species integrity can only be maintained through post-zygotic isolating barriers (PIBs). PIBs need not only be intrinsic (i.e. hybrid inviability and sterility caused by developmental incompatibilities), but also can be extrinsic due to the hybrid's intermediate phenotype falling between the parental niches. For example, in migratory species, hybrid fitness might be reduced as a result of intermediate migration pathways and reaching suboptimal wintering grounds. Here, we test this idea by comparing the juvenile to adult survival probabilities as well as the wintering grounds of pied flycatchers (Ficedula hypoleuca), collared flycatchers (Ficedula albicollis) and their hybrids using stable isotope ratios of carbon (delta13C) and nitrogen (delta15N) in feathers developed at the wintering site. Our result supports earlier observations of largely segregated wintering grounds of the two parental species. The isotope signature of hybrids clustered with that of pied flycatchers. We argue that this pattern can explain the high annual survival of hybrid flycatchers. Hence, dominant expression of the traits of one of the parental species in hybrids may substantially reduce the ecological costs of hybridization. 相似文献
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Aurore Ponchon Thomas Cornulier April Hedd Jos Pedro Granadeiro Paulo Catry 《Ecology and evolution》2019,9(15):8702-8713
Pelagic seabirds breeding at high latitudes generally split their annual cycle between reproduction, migration, and wintering. During the breeding season, they are constrained in their foraging range due to reproduction while during winter months, and they often undertake long‐distance migrations. Black‐browed albatrosses (Thalassarche melanophris) nesting in the Falkland archipelago remain within 700 km from their breeding colonies all year‐round and can therefore be considered as resident. Accordingly, at‐sea activity patterns are expected to be adjusted to the absence of migration. Likewise, breeding performance is expected to affect foraging, flying, and floating activities, as failed individuals are relieved from reproduction earlier than successful ones. Using geolocators coupled with a saltwater immersion sensor, we detailed the spatial distribution and temporal dynamics of at‐sea activity budgets of successful and failed breeding black‐browed albatrosses nesting in New Island, Falklands archipelago, over the breeding and subsequent nonbreeding season. The 90% monthly kernel distribution of failed and successful breeders suggested no spatial segregation. Both groups followed the same dynamics of foraging effort both during daylight and darkness all year, except during chick‐rearing, when successful breeders foraged more intensively. Failed and successful breeders started decreasing flying activities during daylight at the same time, 2–3 weeks after hatching period, but failed breeders reached their maximum floating activity during late chick‐rearing, 2 months before successful breeders. Moon cycle had a significant effect on activity budgets during darkness, with individuals generally more active during full moon. Our results highlight that successful breeders buffer potential reproductive costs during the nonbreeding season, and this provides a better understanding of how individuals adjust their spatial distribution and activity budgets according to their breeding performance in absence of migration. 相似文献
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Valerie Chosson;Virginie Wyss;Beatrice Jann;Frederick W. Wenzel;Guðjón Már Sigurðsson;Malene Simon;Rikke Guldborg Hansen;Lindsey S. Jones; 《Ecology and evolution》2024,14(3):e11152
The endangered population of humpback whales (Megaptera novaeangliae) breeding and calving off the Cape Verde Islands (CVI) are known to migrate to feeding areas located along the eastern margin of the North Atlantic Ocean (Iceland, and Norway). Here, we report for the first time a confirmed migration of an individual humpback whale from CVI breeding ground to a western North Atlantic feeding ground of West Greenland. This individual humpback, which was photographed and identified off the coast of West Greenland in 2021, was previously documented in CVI 22 years before (1999). An annual subsistence hunt for humpbacks occurs in West Greenland and the resighting at this location with a humpback whale from CVI has strong implications for the conservation efforts of the small CVI population. 相似文献