scholarly journals Movement ecology of juvenile pond-breeding salamanders : implications for the management and conservation of amphibian populations

2013 ◽  
Author(s):  
Shannon Elisabeth Pittman
Keyword(s):  
Movement Ecology ◽  
Management And Conservation

scholarly journals Migration routes and habitat use of a highly adaptable salmonid (sea trout, Salmo trutta) in a complex marine area

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Martin Lykke Kristensen ◽  
Martin Wæver Pedersen ◽  
Uffe Høgsbro Thygesen ◽  
Diego del Villar-Guerra ◽  
Henrik Baktoft ◽  
...  
Keyword(s):  
Salmo Trutta ◽  
Markov Models ◽  
Movement Ecology ◽  
Optimal Conditions ◽  
Migration Routes ◽  
Marine Area ◽  
Sea Trout ◽  
Marine Areas ◽  
Electronic Tags ◽  
Management And Conservation

Abstract Background Understanding fish movements and migrations are paramount for management and conservation efforts. By applying Hidden Markov Models (HMMs) on records from electronic tags, migration routes of tagged fish can be reconstructed and new insights to the movement ecology of a species can be gained. We demonstrate the usability of HMMs on a widespread, iteroparous salmonid (sea trout, Salmo trutta) in a complex marine area with highly variable temperatures and salinities within small geographic distances. Understanding how the highly adaptable sea trout cope with these complex conditions could shed new light on factors driving the movement ecology of salmonids. Migration tracks of fish migrating at sea are reconstructed by applying an HMM on temperature and depth records from eight wild post-spawned sea trout from four Danish rivers. Results The fish migrated at sea for 47–142 days. Estimated positions of all fish were close to the coast (< 100 km) throughout the marine period, but migrations along coastlines up to 580 km away from the natal river occurred. Seven of eight individuals resided in or actively migrated into stratified or shallow marine areas that heat up fast during spring, while all eight individuals resided in deeper and more heterogeneous areas that heat up slow during summer. All fish entered the Skagerrak (located between Denmark and Norway) at some stage during summer. Migrations were directed into less saline areas during the first 15 days at sea for all individuals. Mean linear progression of the fish was 16 km day−1 (range 0–58 km day−1). Conclusions The results corroborate the expectation that sea trout are more coastally orientated than other salmonids, but also suggest that longer migrations occur in the seas surrounding Denmark compared to elsewhere. This could be a consequence of the fish seeking out habitats with optimal conditions (e.g. salinity, temperature, predation and foraging options) for growth in different parts of the year. The coinciding movement from shallow or stratified marine areas that heat up fast during spring to deeper, more well-mixed areas that heat up slow during summer suggested that some habitat selection had occurred. These results shed new light on factors influencing marine migrations in salmonids and demonstrate how HMMs can expand our knowledge on behaviour and movement ecology of marine fishes.

Documentation et gestion du patrimoine archéologique de la chaîne montagneuse tuniso-libyenne via l'utilisation des nouvelles technologies : résultats préliminaires

2021 ◽  
pp. 1-16
Author(s):  
Héla Mekki
Keyword(s):  
New Technologies ◽  
Management Plan ◽  
Archaeological Sites ◽  
Mountain Range ◽  
Direct Evaluation ◽  
Nouvelles Technologies ◽  
Data Assessment ◽  
Conservation Plan ◽  
Indirect Evaluation ◽  
Management And Conservation

Abstract The mountain range formed by Jebels Matmata, Demmer and Nefoussa which links the two countries, Tunisia and Libya, is strewn with archaeological remains that are little known today, due in part to the rugged terrain which makes it difficult to see them. This issue has been helped by the use of new technologies, in this case remote sensing and QGIS software. Archaeological evidence has been uncovered and more than 3,900 sites and monuments have been detected on the sides of these mountains. In addition to the inventory of unknown archaeological sites, the main aim of the work was to draw up a management and conservation plan to provide, with an order of priority, a strategy for the safeguard and conservation of the mountain heritage. This management plan was only possible through a correlation of three data: assessment of values, identification of threats, and study of the state of conservation. These components were studied using an indirect evaluation based on satellite imagery and direct evaluation through field visits.

Prioritizing strain insulators for raptor conservation

2021 ◽  
pp. 1-16
Author(s):  
FRANCISCO GUIL ◽  
M. ÁNGELES SORIA ◽  
VÍCTOR ORTEGA ◽  
RUBÉN GARCÍA-SÁNCHEZ ◽  
SILVIA VILLAVERDE-MORCILLO
Keyword(s):  
Methodological Approach ◽  
Risk Index ◽  
Influential Factors ◽  
Negative Effects ◽  
Central Spain ◽  
Novel Approach ◽  
Conservation Actions ◽  
Complete Survey ◽  
Raptor Conservation ◽  
Management And Conservation

Summary Avian species often take advantage of human-made structures, such as perching on power poles, although this can lead to negative effects for both birds and infrastructure. It has been demonstrated that anchor-type pylons, with strain insulators, are amongst the most dangerous of these structures. Our goal was to develop a methodological approach to evaluate the ways in which raptors perch on the six most commonly used strain insulator configurations in Spain, and to build a risk index that can be used to prioritise them. To study the ways raptors perch, we worked with six wildlife rescue centres in central Spain for almost a year assessing these six strain insulator configurations in 83 perch trials with 176 raptors in ample flying pens. We analysed 475 complete survey days, with an approximate number of 258,960 analysed pictures, including 6,766 perchings on strain insulators. We assessed the influential factors for these 6,766 perchings and developed a novel approach to prioritise strain insulator configurations that can be used anywhere. Our results suggest that longer insulator strains (i.e. PECA-1000 and Caon-C3670) are the safest, according to our prioritization criteria, although these results require further assessment in the field. Managers and conservationists should take into account these results to improve management and conservation actions.

scholarly journals In-air hearing in Hawaiian monk seals: implications for understanding the auditory biology of Monachinae seals

2021 ◽  
Author(s):  
Brandi Ruscher ◽  
Jillian M. Sills ◽  
Beau P. Richter ◽  
Colleen Reichmuth
Keyword(s):  
Marine Mammals ◽  
Elephant Seal ◽  
Critical Ratio ◽  
Mirounga Angustirostris ◽  
Northern Elephant Seal ◽  
Hearing Ability ◽  
Highly Sensitive ◽  
Monk Seals ◽  
Management And Conservation ◽  
Hearing Abilities

AbstractThe auditory biology of Monachinae seals is poorly understood. Limited audiometric data and certain anatomical features suggest that these seals may have reduced sensitivity to airborne sounds compared to related species. Here, we describe the in-air hearing abilities of a Hawaiian monk seal (Neomonachus schauinslandi) trained to participate in a psychophysical paradigm. We report absolute (unmasked) thresholds for narrowband signals measured in quiet conditions across the range of hearing and masked thresholds measured in the presence of octave-band noise at two frequencies. The behavioral audiogram indicates a functional hearing range from 0.1 to 33 kHz and poor sensitivity, with detection thresholds above 40 dB re 20 µPa. Critical ratio measurements are elevated compared to those of other seals. The apparently reduced terrestrial hearing ability of this individual—considered with available auditory data for a northern elephant seal (Mirounga angustirostris)—suggests that hearing in Monachinae seals differs from that of the highly sensitive Phocinae seals. Exploration of phylogenetic relationships and anatomical traits support this claim. This work advances understanding of the evolution of hearing in amphibious marine mammals and provides updated information that can be used for management and conservation of endangered Hawaiian monk seals.

scholarly journals “Micropersonality” traits and their implications for behavioral and movement ecology research

2021 ◽  
Vol 11 (7) ◽  
pp. 3264-3273
Author(s):  
Joseph D. Bailey ◽  
Andrew J. King ◽  
Edward A. Codling ◽  
Ashley M. Short ◽  
Gemma I. Johns ◽  
...  
Keyword(s):  
Movement Ecology
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