Understanding the Risk to Neotropical Migrant Bird Species of Multiple Human-Caused Stressors:  Elucidating Processes Behind the Patterns.

Despite the continuously growing number of known avian picornaviruses (family Picornaviridae), knowledge of their genetic diversity in wild birds, especially in long-distance migrant species is very limited. In this study, we report the presence of a novel picornavirus identified from one of 18 analysed faecal samples of an Afro-Palearctic migrant bird, the European roller (Coracias garrulus L., 1758), which is distantly related to the marine-mammal-infecting seal aquamavirus A1 (genus Aquamavirus). The phylogenetic analyses and the low sequence identity (P1 26.3 %, P2 25.8 % and P3 28.4 %) suggest that this picornavirus could be the founding member of a novel picornavirus genus that we have provisionally named ‘Kunsagivirus’, with ‘Greplavirus A’ (strain roller/SZAL6-KuV/2011/HUN, GenBank accession no. KC935379) as the candidate type species.

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Defining the key wintering habitats in the Sahel for declining African-Eurasian migrants using expert assessment

Bird Conservation International ◽

10.1017/s0959270913000531 ◽

2014 ◽

Vol 24 (4) ◽

pp. 477-491 ◽

Cited By ~ 5

Author(s):

PHILIP W. ATKINSON ◽

WILLIAM M. ADAMS ◽

JOOST BROUWER ◽

GRAEME BUCHANAN ◽

ROBERT A. CHEKE ◽

...

Keyword(s):

Bird Species ◽

Field Studies ◽

Habitat Associations ◽

Expert Assessment ◽

Rapid Decline ◽

Breeding Populations ◽

Western Palearctic ◽

Wintering Area ◽

Declining Species ◽

Migrant Bird

SummaryThe Sahel in West Africa is a major wintering area for many western Palearctic migrants. The breeding populations of many of these have declined over the past 50 years. However, there have been few intensive field studies on migrant ecology in the Sahel and these were generally within a very restricted area. Consequently our knowledge of the distribution of species within this extensive area and the habitat associations of these species is limited. Understanding these habitat associations is essential for the effective conservation management of populations. We brought together a group of experts and consulted a wider group by email to assess the main Sahelian habitat types used by 68 African-Eurasian migrant bird species. Those species that showed strongest declines during 1970–1990 were associated with more open habitats than those newly declining during 1990–2000, when declining species were associated with habitats with more shrubs and trees. Populations of species that winter in the Sahel are generally stable or increasing now as rainfall has increased and is now near the long-term average for the Sahel. Those which use the Sahel only as a staging area are, in many cases, in rapid decline at present.

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Breeding and passage migrant bird species in Kars province

Turkish Journal of Forestry | Türkiye Ormancılık Dergisi ◽

10.18182/tjf.635124 ◽

2020 ◽

pp. 179-187

Author(s):

Ömral Ünsal ÖZKOÇ

Keyword(s):

Bird Species ◽

Migrant Bird

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Efecto de la estacionalidad y lluvias en la avifauna del Chaco Serrano Austral, Argentina

Revista de Biología Tropical ◽

10.15517/rbt.v65i3.29434 ◽

2017 ◽

Vol 65 (3) ◽

pp. 953

Author(s):

Gustavo Alfredo Fava ◽

Juan Carlos Acosta ◽

Graciela Mirta Blanco

Keyword(s):

Bird Species ◽

Reproductive Activity ◽

Breeding Habitat ◽

Bird Abundance ◽

Group Management ◽

Natural Park ◽

Chaco Serrano ◽

Site Survey ◽

Migrant Bird ◽

Resident Bird

In subtropical regions like the Chaco Serrano (33° S), rainfall has a marked seasonality, and water flood, caused by heavy rains, may have important consequences for dependent ecosystems. Conversely, the high pressure on available resources during dry periods can also affect the fauna diversity and distribution. Even though birds have shown to be excellent ecological indicators of these shifts in the environment, currently little is known about the avifauna of the Argentine Chaco Serrano phytogeographic district. Our aim was to study the resident bird population status in the Southern Chaco Serrano, its fluctuations in richness and abundance, and its relationship to seasonal variations, in monthly and annual hydroperiods. In order to assess the resident bird status over a two year period (2011 Mar.-2013 Feb.) we carried out 18 sampling surveys during pre-breeding (spring), breeding (summer) and non breeding periods (autumn-winter), in the Northeastern part of the Valle Fértil Natural Park, San Juan province, Argentina. During each site survey, we recorded bird assemblages found in six transects, and obtained bird abundance and species diversity. A mixed general linear model was employed to evaluate relationships between the studied variables. We found a total of 98 species of birds belonging to 33 families (44 resident species, 23 spring visitors, six summer visitors, two winter visitors and 23 with scarce registers). We also registered 68 of these species in both hydroperiods, 28 only during rainy periods and only two during the dry period. Both richness and abundance showed the highest values during the pre-breeding and rainy seasons, while different tendencies were detected during the isolated monthly rainfalls. These changes in bird densities were associated with the arrival of migratory species, mainly spring visitors, and probably in relationship with their reproductive activity, and to seasonal fluctuations in food resources. The Southern Chaco Serrano is a subtropical semiarid place that seems to be an important breeding habitat for many migrant bird species, which in turn promoted seasonal changes in species density and diversity, mainly during rainy years. This work contributed to our understanding on the causes of richness and abundance variations on birds, and will contribute to this important group management and conservation in this area.

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Assessing conservation status of resident and migrant birds on Hispaniola with constant-effort mist-netting

10.7287/peerj.preprints.1368v1 ◽

2015 ◽

Author(s):

John D Lloyd ◽

Chris C Rimmer ◽

Kent P McFarland

Keyword(s):

Population Change ◽

Conservation Status ◽

Capture Rate ◽

Temporal Trends ◽

Bird Species ◽

Quantitative Information ◽

Neotropical Migrant ◽

Migrant Birds ◽

Conservation Assessments ◽

Capture Rates

We analyzed temporal trends in mist-net capture rates of resident (n = 8) and overwintering Nearctic-Neotropical migrant (n = 3) bird species at two sites in montane broadleaf forest of the Sierra de Bahoruco, Dominican Republic, with the goal of providing quantitative information on population trends that could inform conservation assessments. We conducted sampling at least once annually during the winter months of January – March from 1997 – 2010. We found evidence of steep declines in capture rates for three resident species, including one species endemic to Hispaniola. Capture rate of Rufous-throated Solitaire (Myadestes genibarbis) declined by 3.9% per year (95% CL = 0%, 7.3%), Green-tailed Ground-Tanager (Microlegia palustris) by 6.8% (95% CL = 3.9%, 8.8%), and Greater Antillean Bullfinch (Loxigilla violacea) by 4.9% (95% CL = 0.9%, 9.2%). Two rare and threatened endemics, Hispaniolan Highland-Tanager (Xenolegia montana) and Western Chat-Tanager (Calyptophilus tertius), showed statistically significant declines, but we have low confidence in these findings because trends were driven by exceptionally high capture rates in 1997 and varied between sites. Analyses that excluded data from 1997 revealed no trend in capture rate over the course of the study. We found no evidence of temporal trends in capture rates for any other residents or Nearctic-Neotropical migrants. We do not know the causes of the observed declines, nor can we conclude that these declines are not a purely local phenomenon. However, our findings, along with other recent reports of declines in these same species, suggest that a closer examination of their conservation status is warranted. Given the difficulty in obtaining spatially extensive, long-term estimates of population change for Hispaniolan birds, we suggest focusing on other metrics of vulnerability that are more easily quantified yet remain poorly described, such as extent of occurrence.

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Assessing conservation status of resident and migrant birds on Hispaniola with mist-netting

PeerJ ◽

10.7717/peerj.1541 ◽

2016 ◽

Vol 3 ◽

pp. e1541 ◽

Cited By ~ 2

Author(s):

John D. Lloyd ◽

Christopher C. Rimmer ◽

Kent P. McFarland

Keyword(s):

Population Change ◽

Conservation Status ◽

Capture Rate ◽

Temporal Trends ◽

Bird Species ◽

Quantitative Information ◽

Neotropical Migrant ◽

Migrant Birds ◽

Conservation Assessments ◽

Capture Rates

We analyzed temporal trends in mist-net capture rates of resident (n= 8) and overwintering Nearctic-Neotropical migrant (n= 3) bird species at two sites in montane broadleaf forest of the Sierra de Bahoruco, Dominican Republic, with the goal of providing quantitative information on population trends that could inform conservation assessments. We conducted sampling at least once annually during the winter months of January–March from 1997 to 2010. We found evidence of declines in capture rates for three resident species, including one species endemic to Hispaniola. Capture rate of Rufous-throated Solitaire (Myadestes genibarbis) declined by 3.9% per year (95% CL = 0%, 7.3%), Green-tailed Ground-Tanager (Microligea palustris) by 6.8% (95% CL = 3.9%, 8.8%), and Greater Antillean Bullfinch (Loxigilla violacea) by 4.9% (95% CL = 0.9%, 9.2%). Two rare and threatened endemics, Hispaniolan Highland-Tanager (Xenoligea montana) and Western Chat-Tanager (Calyptophilus tertius), showed statistically significant declines, but we have low confidence in these findings because trends were driven by exceptionally high capture rates in 1997 and varied between sites. Analyses that excluded data from 1997 revealed no trend in capture rate over the course of the study. We found no evidence of temporal trends in capture rates for any other residents or Nearctic-Neotropical migrants. We do not know the causes of the observed declines, nor can we conclude that these declines are not a purely local phenomenon. However, our findings, along with other recent reports of declines in these same species, suggest that a closer examination of their conservation status is warranted. Given the difficulty in obtaining spatially extensive, long-term estimates of population change for Hispaniolan birds, we suggest focusing on other metrics of vulnerability that are more easily quantified yet remain poorly described, such as extent of occurrence.

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Evidence of avian-mediated long distance dispersal in American tardigrades

PeerJ ◽

10.7717/peerj.5035 ◽

2018 ◽

Vol 6 ◽

pp. e5035 ◽

Cited By ~ 10

Author(s):

Matthew J. Mogle ◽

Scott A. Kimball ◽

William R. Miller ◽

Richard D. McKown

Keyword(s):

Bird Species ◽

Distribution Patterns ◽

Long Distance Dispersal ◽

Long Distance ◽

Neotropical Migrant ◽

Grus Canadensis ◽

Sandhill Crane ◽

Migrant Birds ◽

North And South

Terrestrial tardigrades, commonly known as “water bears”, are part of a phylum of microscopic, aquatic invertebrates famous for cryptobiosis and space travel, but little is known about their modes of dispersal on Earth. Wind is assumed, but not truly demonstrated, to be the major method of global dispersal. Yet, some water bear distribution patterns cannot be explained by patterns of prevailing winds. Mammals and birds have been proposed as potential animal vectors. Importantly, most nearctic-neotropical migrant birds move north and south, with many crossing the equator, whereas prevailing winds move west to east or east to west but do not cross the equator. When multiplied by billions of birds over tens of millions of years, if the ectozoochory of tardigrades by birds is true then both regional and intercontinental patterns can be better explained. To test for the potential role of birds in tardigrade dispersal, the nests of 10 species for birds were examined. Seventy percent of nests were positive for tardigrades, demonstrating that some birds are in a position for transference. The carcasses of eight birds (six species) found dead from window strikes and a Sandhill Crane (Grus canadensis) found dead during routine surveys were also examined. Of the birds examined, 66% yielded tardigrades from two classes, three orders, and five species, including juveniles, adults, and eggs, suggesting that many bird species are potential vectors for many species of tardigrades. Our data support the hypothesis of avian-mediated long distance dispersal of tardigrades and provide evidence that further investigation is warranted.

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Edge Effect on Nesting Success of Ground Nesting Birds Near Regenerating Clearcuts in a Forest-Dominated Landscape

The Auk ◽

10.1093/auk/119.4.955 ◽

2002 ◽

Vol 119 (4) ◽

pp. 955-970 ◽

Cited By ~ 5

Author(s):

James C. Manolis ◽

David E. Andersen ◽

Francesca J. Cuthbert

Keyword(s):

Edge Effect ◽

Edge Effects ◽

Bird Species ◽

Timber Harvest ◽

Agricultural Landscapes ◽

Nesting Success ◽

Population Declines ◽

North Central ◽

Neotropical Migrant ◽

Ground Nesting

Abstract Forest fragmentation has been implicated as a cause of population declines of several Neotropical migrant bird species. Fragmentation increases the amount of habitat edge, and reduced nesting success rates near forest edges are well documented in agricultural landscapes (“edge effects”). However, edge effects in predominantly forested landscapes, particularly those related to timber harvest, are poorly understood. This study examines nesting success of ground nesting birds in relation to clearcut edges in a forest-dominated landscape in north-central Minnesota. A total of 383 nests of seven species of ground nesting birds were found and monitored during 1992–1998. Ovenbird (Seiurus aurocapilus; n = 318) and Hermit Thrush (Catharus guttatus; n = 44) nests composed the majority of the sample. Predation accounted for 94% of all nest failures. Brown-headed Cowbird (Molothrus ater) parasitism was low (1.8% for all ground nests). Using proportional hazards regression, distance to nearest clearcut edge was the best predictor of nest failure. For all ground nests, nesting success was 0.18 at 0–100 m, 0.39 at 101–500 m, and 0.52 at 501–954 m from nearest clearcut edge. Source–sink modeling indicated that distances ≤100 m from clearcut edges were sink habitats for Ovenbirds (i.e. recruitment was lower than survival). These results provide strong evidence of a negative edge effect on ground nests, extending 100 m or more from clearcut edges in a forest-dominated area of north-central Minnesota.

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