Changes in wetland habitat use by waterbirds wintering in Czechia are related to diet and distribution changes

2021 ◽  
Author(s):  
Zuzana Musilová ◽  
Petr Musil ◽  
Jan Zouhar ◽  
Adéla Šenkýřová ◽  
Diego Pavón‐Jordán ◽  
...  
Keyword(s):  
2019 ◽  
Vol 29 (03) ◽  
pp. 463-478 ◽  
Author(s):  
ROBIN B. COLYN ◽  
ALASTAIR CAMPBELL ◽  
HANNELINE A. SMIT-ROBINSON

SummaryThe ‘Critically Endangered’ White-winged Flufftail Sarothrura ayresi is regarded as one of the rarest and most threatened rallids in Africa. Due to the species’ low density, habitat preference, cryptic colouration, elusive behaviour and lack of auditory cues has resulted in it being one of the most challenging species to survey using traditional methods such as auditory surveys and rope dragging. Numerous data deficiencies exist regarding facets of the species’ ecology, distribution, habitat-use and population status. A stratified array of nine camera localities was used within high-altitude palustrine wetland habitat to ascertain if this non-invasive technique could successfully document the first estimate of site occupancy, fine scale habitat use and activity patterns of this very rare species. Our study accumulated a total of 626 camera days and eight independent sightings of White-winged Flufftail across the respective austral summer season. Furthermore, our study confirms the applicability of camera trapping to other rare and elusive rallid species. Our results confirm that White-winged Flufftail is a low-density habitat specialist species, with site occupancy influenced positively by basal and canopy vegetation cover and detection probability influenced negatively by water depth within associated wetland habitats. Activity pattern analyses displayed that peak activity occurred at dawn and dusk, which yielded the highest degree of activity overlap with the only other migratory rallid recorded, Spotted Crake Porzana prozana. Our study also recorded the first apparent territorial display behaviour noted for the species. Our study supports the need for conservation initiatives focused on securing contiguous sections of suitable wetland habitat in order to accommodate the persistence of this globally threatened species.


The Condor ◽  
1999 ◽  
Vol 101 (2) ◽  
pp. 282-287 ◽  
Author(s):  
Michael W. Ritter ◽  
Julie A. Savidge

2016 ◽  
Vol 544 ◽  
pp. 197-211 ◽  
Author(s):  
A Chin ◽  
MR Heupel ◽  
CA Simpfendorfer ◽  
AJ Tobin

2019 ◽  
Vol 609 ◽  
pp. 239-256 ◽  
Author(s):  
TL Silva ◽  
G Fay ◽  
TA Mooney ◽  
J Robbins ◽  
MT Weinrich ◽  
...  

2020 ◽  
Vol 642 ◽  
pp. 227-240
Author(s):  
L Lodi ◽  
R Tardin ◽  
G Maricato

Most studies of cetacean habitat use do not consider the influence of anthropogenic activities. We investigated the influence of environmental and anthropogenic variables on habitat use by humpback Megaptera novaeangliae and Bryde’s whales Balaenoptera brydei off the coast of the Brazilian city of Rio de Janeiro. Although there are 2 marine protected areas (MPAs) in this area, few data are available on cetacean habitat use or on the overlap of different cetacean species within these MPAs. Our aim was to evaluate the effectiveness of the MPAs and propose a buffer zone to better protect the biodiversity of the study area. We conducted systematic surveys and developed spatial eigenvector generalized linear models to characterize habitat use by the species in the study area. Habitat use by humpback whales was influenced only by depth, whereas for Bryde’s whales there was the additional influence of anthropogenic variables. For Bryde’s whales, which use the area for feeding, sea surface temperature and the distance to anchorages had a major influence on habitat use. We also showed that neither of the MPAs in the study area adequately protects the hotspots of either whale species. Most of the humpback whale grid cells with high sighting predictions were located within 2 km of the MPAs, while areas of high sighting prediction of Bryde’s whales were located up to 5 km from the MPAs, closer to beaches. Our findings provide important insights for the delimitation of protected areas and zoning of the MPAs.


2020 ◽  
Vol 639 ◽  
pp. 169-183
Author(s):  
P Matich ◽  
BA Strickland ◽  
MR Heithaus

Chronic environmental change threatens biodiversity, but acute disturbance events present more rapid and immediate threats. In 2010, a cold snap across south Florida had wide-ranging impacts, including negative effects on recreational fisheries, agriculture, and ecological communities. Here, we use acoustic telemetry and historical longline monitoring to assess the long-term implications of this event on juvenile bull sharks Carcharhinus leucas in the Florida Everglades. Despite the loss of virtually all individuals (ca. 90%) within the Shark River Estuary during the cold snap, the catch per unit effort (CPUE) of age 0 sharks on longlines recovered through recruitment within 6-8 mo of the event. Acoustic telemetry revealed that habitat use patterns of age 0-2 sharks reached an equilibrium in 4-6 yr. In contrast, the CPUE and habitat use of age 3 sharks required 5-7 yr to resemble pre-cold snap patterns. Environmental conditions and predation risk returned to previous levels within 1 yr of the cold snap, but abundances of some prey species remained depressed for several years. Reduced prey availability may have altered the profitability of some microhabitats after the cold snap, leading to more rapid ontogenetic shifts to marine waters among sharks for several years. Accelerated ontogenetic shifts coupled with inter-individual behavioral variability of bull sharks likely led to a slower recovery rate than predicted based on overall shark CPUE. While intrinsic variation driven by stochasticity in dynamic ecosystems may increase the resistance of species to chronic and acute disturbance, it may also increase recovery time in filling the diversity of niches occupied prior to disturbance if resistive capacity is exceeded.


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