Spring migration patterns, habitat use, and stopover site protection status for two declining waterfowl species wintering in China as revealed by satellite tracking

SummaryThe use of forest habitats and migratory patterns are still unclear for tropical birds. Some are described herein for the Pantanal wetlands of Brazil. Thus, our aim was to describe different patterns of forest habitat use by birds and classify the birds’ migration patterns for the northern Pantanal region, Brazil. From September 1999 to December 2003, we sampled four forest types, during which we collected standardised data with mist-net captures and point counts, with additional ad lib. observations. We recorded 214 bird species: 113 (52.8%) were total habitat generalists; 41 (19.2%) were forest generalists; 19 (8.9%) were flooded habitat specialists; and 28 (13.1%) were not classified due to the low number of records; three other categories of habitat use divide the remaining 6% of records. About half of the species showed some migratory behaviour, these were classified by us according to the season they spent in the area: 121 species (56.5%) as residents, 28 (13.1%) as run-off and dry migrants, 11 (5.1%) as run-off (winter) migrants, eight (3.7%) as dry (breeding) migrants, eight (3.7%) as dry and flooding (summer) migrants, eight (3.7%) as flooding migrants, three (1.4%) as flooding and run-off migrants, and 27 (12.6%) as uncommon. We constructed community occupancy models with six of the eight patterns of migration described; flooding migrants and run-off migrants were not modelled since the few species recorded also had very few detections. As expected, the model confirmed that species from all six tested migration patterns arrive and depart from the Pantanal across the seasons. Contrary to most Neotropical forests, there was a high percentage (43.5%) of non-resident species. The results show the need of investing heavily in preserving different landscape units within the Pantanal, but also in the surrounding Cerrado region, in order to conserve resident and short distance intra-tropical migrants.

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Relationship between energetic condition and indicators of immune function in thrushes during spring migration

Canadian Journal of Zoology ◽

10.1139/z08-038 ◽

2008 ◽

Vol 86 (7) ◽

pp. 638-647 ◽

Cited By ~ 36

Author(s):

J. C. Owen ◽

F. R. Moore

Keyword(s):

Immune Response ◽

Immune Function ◽

Spring Migration ◽

Hylocichla Mustelina ◽

Catharus Ustulatus ◽

Stopover Site ◽

Lymphocyte Ratio ◽

Energetic Condition ◽

In Captivity ◽

Immunoglobulin Gamma

Evidence suggests that the ability of an animal to maintain its immune system and (or) mount an immune response depends on its nutritional health and energetic condition. Migration is a period within an animal’s annual cycle when energetic condition varies, especially after a long, nonstop flight over a large ecological barrier. Our objective was to determine if measures of immune function in migrating Wood Thrush ( Hylocichla mustelina (J.F. Gmelin, 1789)), Swainson’s Thrush ( Catharus ustulatus (Nuttall, 1840)), Gray-cheeked Thrush ( Catharus minimus (Lafresnaye, 1848)), and Veery ( Catharus fuscescens (Stephens, 1817)) were related to the energetic condition of the birds at a stopover site during spring migration. We present data on total leukocyte, lymphocyte, and heterophil counts, heterophil/lymphocyte ratio, serum immunoglobulin gamma G (IgG) concentration, and immune response to phytohemagglutinin. Thrushes arriving at the stopover site in poor energetic condition had low leukocyte and lymphocyte counts. Heterophil/lymphocyte ratio, heterophil count, and IgG concentration were not related to energetic condition. Furthermore, immune response to phytohemagglutinin was positively related to change in mass and days spent in captivity, suggesting that immune function may improve during stopover. We suggest that migrating thrushes arriving at a stopover site in poor energetic condition may also be in poor immunological condition and may have increased susceptibility to disease or parasite infection.

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Social foraging and habitat use by a long-distance passerine migrant, Whinchat Saxicola rubetra, at a spring stopover site on the SE Adriatic coast

Journal of Ornithology ◽

10.1007/s10336-010-0506-z ◽

2010 ◽

Vol 151 (3) ◽

pp. 655-663 ◽

Cited By ~ 1

Author(s):

Urša Koce ◽

Damijan Denac

Keyword(s):

Habitat Use ◽

Social Foraging ◽

Long Distance ◽

Stopover Site ◽

Saxicola Rubetra ◽

Adriatic Coast ◽

Spring Stopover

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Water column structure influences long-distance latitudinal migration patterns and habitat use of bumphead sunfish Mola alexandrini in the Pacific Ocean

Scientific Reports ◽

10.1038/s41598-021-01110-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ching-Tsun Chang ◽

Wei-Chuan Chiang ◽

Michael K. Musyl ◽

Brian N. Popp ◽

Chi Hin Lam ◽

...

Keyword(s):

Habitat Use ◽

Water Column ◽

New Caledonia ◽

Long Distance ◽

Okinawa Island ◽

Migration Patterns ◽

Vertical Movements ◽

Near Surface ◽

The Pacific ◽

Utilization Patterns

AbstractSatellite-tracking of adult bumphead sunfish, Mola alexandrini, revealed long-distance latitudinal migration patterns covering thousands of kilometers. Horizontal and vertical movements of four bumphead sunfish off Taiwan were recorded with pop-up satellite archival tags in 2019–2020. Two individuals moved northward and traveled to Okinawa Island and Kyushu, Japan and two moved southwards; crossing the equator, to Papua New Guinea and New Caledonia. During daytime, bumphead sunfish descended below the thermocline and ascended to mixed layer depths (MLD) during nighttime. The N–S migrants, however, demonstrated different habitat utilization patterns. Instead of using prevailing currents, the northward movements of sunfish cohorts exhibited extensive use of mesoscale eddies. Fish in anticyclonic eddies usually occupied deeper habitats whereas those in cyclonic eddies used near-surface habitats. On northward excursions, fish spent most of their time in regions with high dissolved oxygen concentrations. Southward movement patterns were associated with major currents and thermal stratification of the water column. In highly stratified regions, fish stayed below the thermocline and frequently ascended to MLD during daytime either to warm muscles or repay oxygen debts. These results for bumphead sunfish present important insights into different habitat use patterns and the ability to undergo long-distance migrations over varying spatial-temporal scales and features.

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