scholarly journals Multiple-threats analysis for loggerhead sea turtles in the southwest Atlantic Ocean

2020 ◽  
Vol 41 ◽  
pp. 183-196 ◽  
Author(s):  
M López-Mendilaharsu ◽  
B Giffoni ◽  
D Monteiro ◽  
L Prosdocimi ◽  
GM Vélez-Rubio ◽  
...  
Keyword(s):  
Sea Turtles ◽  
Life Stages ◽  
Loggerhead Sea Turtles ◽  
Southwest Atlantic ◽  
Trawl Fishery ◽  
Threat Analysis ◽  
Species Of Conservation Concern ◽  
Terrestrial Environments ◽  
Fisheries Bycatch ◽  
Conservation Concern

Priority-setting approaches for widely distributed and long-lived species can be challenging. This is especially true for sea turtles, which are species of conservation concern. The aim of this study was to conduct a detailed analysis of threats to identify, quantify and prioritize the main impacts to the loggerhead Caretta caretta population in the southwest Atlantic (SWA) region. A matrix of relative threats was constructed. Threats were identified and classified for 8 different life stages (nesting females, eggs, hatchlings, swim-frenzy transitional stage, juveniles-neritic, juveniles-oceanic, adults-neritic, adults-oceanic) and for 3 ecosystems inhabited by sea turtles (terrestrial, neritic and oceanic). Results indicated that fisheries bycatch represents a major threat for loggerheads in the SWA. The trawl fishery was identified as the main source of mortality for neritic juvenile and adult turtles, whereas juveniles in oceanic areas are mostly impacted by surface longlines. In terrestrial environments, eggs and hatchlings are mainly affected by habitat alteration and by native and exotic predators. Loggerheads have shown a positive nesting trend at their main nesting beaches in the SWA, probably due to long-term conservation efforts to reduce mortality of the different life stages within the terrestrial zone. However, the high mortality rates of juveniles and sub-adults documented at some known foraging grounds represent a reason for concern, as this may affect the overall population trend in the future. This threat analysis provides a tool to review the goals of national action plans, prioritize actions and optimize the allocation of management resources.

scholarly journals Incorporating Geographical Scale and Multiple Environmental Factors to Delineate the Breeding Distribution of Sea Turtles

Drones ◽  
2021 ◽  
Vol 5 (4) ◽  
pp. 142
Author(s):  
Liam C. Dickson ◽  
Kostas A. Katselidis ◽  
Christophe Eizaguirre ◽  
Gail Schofield
Keyword(s):  
Sea Turtles ◽  
Regional Distribution ◽  
Environmental Parameters ◽  
Environmental Data ◽  
Offshore Wind ◽  
Loggerhead Sea Turtles ◽  
Change Models ◽  
Terrestrial Environments ◽  
Aircraft System ◽  
Marine Megafauna

Temperature is often used to infer how climate influences wildlife distributions; yet, other parameters also contribute, separately and combined, with effects varying across geographical scales. Here, we used an unoccupied aircraft system to explore how environmental parameters affect the regional distribution of the terrestrial and marine breeding habitats of threatened loggerhead sea turtles (Caretta caretta). Surveys spanned four years and ~620 km coastline of western Greece, encompassing low (<10 nests/km) to high (100–500 nests/km) density nesting areas. We recorded 2395 tracks left by turtles on beaches and 1928 turtles occupying waters adjacent to these beaches. Variation in beach track and inwater turtle densities was explained by temperature, offshore prevailing wind, and physical marine and terrestrial factors combined. The highest beach-track densities (400 tracks/km) occurred on beaches with steep slopes and higher sand temperatures, sheltered from prevailing offshore winds. The highest inwater turtle densities (270 turtles/km) occurred over submerged sandbanks, with warmer sea temperatures associated with offshore wind. Most turtles (90%) occurred over nearshore submerged sandbanks within 10 km of beaches supporting the highest track densities, showing the strong linkage between optimal marine and terrestrial environments for breeding. Our findings demonstrate the utility of UASs in surveying marine megafauna and environmental data at large scales and the importance of integrating multiple factors in climate change models to predict species distributions.

Climatic Variables Differentially Influence Neotropical Plant Species of Conservation Concern

2021 ◽  
pp. 1-16
Author(s):  
Pablo Antúnez ◽  
Christian Wehenkel ◽  
Collins Byobona Kukunda ◽  
José Ciro Hernández-Díaz
Keyword(s):  
Plant Species ◽  
Climatic Variables ◽  
Species Of Conservation Concern ◽  
Conservation Concern

Using impact assessment study designs for addressing impacts to species of conservation concern

2012 ◽  
Vol 36 (3) ◽  
pp. 450-456 ◽  
Author(s):  
Mike E. Marshall ◽  
Ashley M. Long ◽  
Shannon L. Farrell ◽  
Heather A. Mathewson ◽  
Michael L. Morrison ◽  
...  
Keyword(s):  
Impact Assessment ◽  
Impact Assessment Study ◽  
Assessment Study ◽  
Species Of Conservation Concern ◽  
Conservation Concern ◽  
Study Designs

scholarly journals White-nose syndrome-related changes to Mid-Atlantic bat communities across an urban-to-rural gradient

BMC Zoology ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Sabrina Deeley ◽  
Joshua B. Johnson ◽  
W. Mark Ford ◽  
J. Edward Gates
Keyword(s):  
The United States ◽  
Myotis Lucifugus ◽  
National Capital Region ◽  
Conservation Areas ◽  
White Nose Syndrome ◽  
Species Of Conservation Concern ◽  
National Capital ◽  
Park Service ◽  
Bat Conservation ◽  
Conservation Concern

Abstract Background White-nose Syndrome (WNS) has reduced the abundance of many bat species within the United States’ Mid-Atlantic region. To determine changes within the National Park Service National Capital Region (NCR) bat communities, we surveyed the area with mist netting and active acoustic sampling (2016–2018) and compared findings to pre-WNS (2003–2004) data. Results The results indicated the continued presence of the threatened Myotis septentrionalis (Northern Long-eared bat) and species of conservation concern, including Perimyotis subflavus (Tri-colored bat), Myotis leibii (Eastern Small-footed bat) and Myotis lucifugus (Little Brown bat). However, we documented a significant reduction in the abundance and distribution of M. lucifugus and P. subflavus, a decrease in the distribution of M. septentrionalis, and an increase in the abundance of Eptesicus fuscus (Big Brown bat). Conclusions Documented post-WNS M. septentrionalis recruitment suggests that portions of the NCR may be important bat conservation areas. Decreases in distribution and abundance of P. subflavus and M. lucifugus indicate probable extirpation from many previously occupied portions of the region.

scholarly journals Deep genetic structure at a small spatial scale in the endangered land snail Xerocrassa montserratensis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Cristina Català ◽  
Vicenç Bros ◽  
Xavier Castelltort ◽  
Xavier Santos ◽  
Marta Pascual
Keyword(s):  
Genetic Structure ◽  
Land Snail ◽  
Snail Species ◽  
Small Spatial Scale ◽  
Geographic Ranges ◽  
Genetic Groups ◽  
Species Of Conservation Concern ◽  
Conservation Actions ◽  
Conservation Concern ◽  
Single Locality

AbstractSpecies with small geographic ranges do not tend to have a high genetic structure, but some land snail species seem to be an exception. Xerocrassa montserratensis, an endangered land snail endemic to Catalonia (northeastern Iberian Peninsula), is an excellent model to study the processes affecting the phylogeography of specialized species of conservation concern. This species is restricted to xerophilous stony slopes and occurs within a small and fragmented area of ca. 500 km2. We sequenced the COI barcode region of 152 individuals from eight sites covering the entire range of the species. We found four genetic groups mostly coincident with their geographic distribution: a central ancestral group containing shared haplotypes among five localities and three groups restricted to a single locality each. Two of these derived groups were geographically and genetically isolated, while the third and most differentiated group was not geographically isolated. Geomorphologic and paleoclimatic processes during the Pleistocene can explain the divergence found between populations of this low dispersal species with historical fragmentation and secondary contacts. Nonetheless, recent passive large dispersal through streams was also detected in the central group. Overall, our study uncovered four evolutionary units, partially matching morphologically described subspecies, which should be considered in future conservation actions.

Integrating citizen science and remotely sensed data to help inform time-sensitive policy decisions for species of conservation concern

2019 ◽  
Vol 237 ◽  
pp. 463-469 ◽  
Author(s):  
Ashley M. Long ◽  
Brian L. Pierce ◽  
Amanda D. Anderson ◽  
Kevin L. Skow ◽  
Addie Smith ◽  
...  
Keyword(s):  
Citizen Science ◽  
Remotely Sensed ◽  
Policy Decisions ◽  
Remotely Sensed Data ◽  
Species Of Conservation Concern ◽  
Conservation Concern

scholarly journals Using a capture-recapture approach for modelling the detectability and distribution of Houbara Bustard in southern Tunisia

2011 ◽  
Vol 22 (3) ◽  
pp. 288-298 ◽  
Author(s):  
M. CHAMMEM ◽  
S. SELMI ◽  
T. KHORCHANI ◽  
S. NOUIRA
Keyword(s):  
Regression Analyses ◽  
Species Occurrence ◽  
Imperfect Detection ◽  
Southern Tunisia ◽  
Species Of Conservation Concern ◽  
Habitat Factors ◽  
Houbara Bustard ◽  
Capture Recapture ◽  
Conservation Concern ◽  
Free Ranging

SummaryModelling the distribution of species of conservation concern is an important issue in population ecology. Classically, logistic regression analyses are conducted to estimate species’ distributions from detection/non-detection data in a sample of sites and to test for the significance of several environmental variables in predicting the probability of occurrence. These modelling approaches assume that species detection probability is constant and equals one in all sampled sites, which is critical, notably in the case of rare, shy and cryptic species. The capture-recapture-like approach developed by Mackenzie et al. (2002, 2003) provides a reliable tool that accounts for imperfect detection when estimating species occurrence, as well as for assessing the relevance of site features as predictors of species occurrence probability. The aim of this study was to explore the possibility of using this approach in the context of Houbara Bustard Chlamydotis undulata in southern Tunisia. Our results show once more the low detectability of this emblematic species and stress the need to take this factor into account when estimating Houbara spatial distribution. The distribution of Houbara in southern Tunisia is more likely to be shaped by human-related than by habitat factors. In particular, Houbara occurrence was positively associated with site remoteness and camel numbers. Houbara seemed to avoid areas with high human presence and shared the most remote and agriculture-free zones with free-ranging camels.

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