Explanipedia

Estimating the detection probability of long-ranging baleen whale song using a single sensor: Towards density estimation Open

Danielle Harris, David K. Mellinger, Kevin D. Heaney, Timothy Clarke, Len Thomas · 2025

Passive acoustic data can be used to estimate animal density. A key step is quantifying the range-specific detection probability for vocalizations from the target species. A method developed to estimate cetacean density from single hydroph…

Spatiotemporal data integration for marine megafauna SDMs in dynamic environments: A point process approach Open

Moritz Klaassen, Marc Fernández, Virginia Morera‐Pujol, Len Thomas, N. Oliveira , et al. · 2025

Species distribution models (SDMs) for marine megafauna, such as cetaceans, traditionally use occurrence data from scientific surveys. These surveys follow standardised protocols and provide spatially structured data, making them a reliabl…

A state-space model for estimating pinniped pup production from serial counts at breeding colonies Open

Eiren K. Jacobson, Mia R. Goldman, Len Thomas, Debbie J. F. Russell · 2025

Factors associated with bycatch of marine mammals in United Kingdom static net fisheries Open

Faye Moyes, Sophie Smout, Len Thomas, Allen Kingston, Simon Northridge · 2025

The accidental capture (‘bycatch’) of marine animals can pose a conservation threat to populations of endangered, threatened, and protected species. We evaluated the factors influencing or associated with estimated bycatch-per-haul (BpH) u…

A State-Space Model for Estimating Pinniped Pup Production from Serial Counts at Breeding Colonies Open

Eiren K. Jacobson, Mia R. Goldman, Len Thomas, Debbie J. F. Russell · 2025

Armando Jaramillo-Legorreta (1964-2024) Open

Lorenzo Rojas‐Bracho, Edwyna Nieto‐Garcia, Gustavo Cárdenas‐Hinojosa, Barbara L. Taylor, Jay Barlow , et al. · 2024

Age is not just a number: How incorrect ageing impacts close‐kin mark‐recapture estimates of population size Open

Felix T. Petersma, Len Thomas, Danielle Harris, Darcy Bradley, Yannis P. Papastamatiou · 2024

Population size is a key parameter for the conservation of animal species. Close‐kin mark‐recapture (CKMR) relies on the observed frequency and type of kinship among individuals sampled from the population to estimate population size. Know…

Estimating age and investigating epigenetic changes related to health across multiple bottlenose dolphin populations Open

Ashley Barratclough, Ryan Takeshita, Len Thomas, Theoni Photopoulou, Enrico Pirotta , et al. · 2024

Funding: This study was partially funded by SERDP grants RC20-C2-1097, RC20-7188 and RC21-3091 awarded to Peter Tyack, Prescott Award NA20NMF4390132 awarded to Ashley Barratclough, and the NOAA Office of Response and Restoration, Assessmen…

Age is not just a number: how incorrect ageing impacts close-kin mark-recapture estimates of population size Open

Felix T. Petersma, Len Thomas, Danielle Harris, Darcy Bradley, Yannis P. Papastamatiou · 2024

Population size is a key parameter for the conservation of animal species. Close-kin mark-recapture (CKMR) relies on the observed frequency and type of kinship among individuals sampled from the population to estimate population size. This…

Decreasing body size is associated with reduced calving probability in critically endangered North Atlantic right whales Open

Enrico Pirotta, Peter L. Tyack, John W. Durban, Holly Fearnbach, Philip K. Hamilton , et al. · 2024

Body size is key to many life-history processes, including reproduction. Across species, climate change and other stressors have caused reductions in the body size to which animals can grow, called asymptotic size, with consequences for de…

Faster inference from state space models via GPU computing Open

Calliste Fagard‐Jenkin, Len Thomas · 2024

Funding: C.F.-J. is funded via a doctoral scholarship from the University of St Andrews, School of Mathematics and Statistics.

Report of the Pollution 2025 - Cumulative Effects - Multiple Stressors IWC Intersessional Workshop Open

Àlex Aguilar, André S. Barreto, A. Valcárcel, Andrew Wright, Angela Recalde‐Salas , et al. · 2024

How to cite: International Whaling Commission, 2023. Report of the Scientific Committee: Report of the Pollution 2025 Workshop. J. Cetacean Res. Manage. (Suppl.) 24: 367-388.

Using individual-based bioenergetic models to predict the aggregate effects of disturbance on populations: A case study with beaked whales and Navy sonar Open

Vincent Hin, André M. de Roos, Kelly J. Benoit‐Bird, Diane Claridge, Nancy DiMarzio , et al. · 2023

Anthropogenic activities can lead to changes in animal behavior. Predicting population consequences of these behavioral changes requires integrating short-term individual responses into models that forecast population dynamics across multi…

Distribution and habitat use modelling from satellite tracking data of humpback whales in Brazil agrees with shipboard survey data modelling Open

Guilherme A. Bortolotto, Alexandre N. Zerbini, Len Thomas, Artur Andriolo, Philip S. Hammond · 2023

Statistical modelling of animal distributions has been widely applied to explain how mobile species use their habitats. The distribution of and habitat use by humpback whales Megaptera novaeangliae off the eastern coast of Brazil have prev…

Accommodating False Positives Within Acoustic Spatial Capture–Recapture, with Variable Source Levels, Noisy Bearings and an Inhomogeneous Spatial Density Open

Felix T. Petersma, Len Thomas, Aaron M. Thode, Danielle Harris, Tiago A. Marques , et al. · 2023

Passive acoustic monitoring is a promising method for surveying wildlife populations that are easier to detect acoustically than visually. When animal vocalisations can be uniquely identified on an array of sensors, the potential exists to…

Vulnerability and resilience of living marine resources to the Deepwater Horizon oil spill: an overview Open

Steven A. Murawski, Patrick Schwing, William F. Patterson, Tracey Sutton, Paul A. Montagna , et al. · 2023

The 2010 Deepwater Horizon (DWH) oil well blowout in the Gulf of Mexico (GoM) was the largest and perhaps most consequential accidental marine oil spill in global history. This paper provides an overview of a Research Topic consisting of f…

Population consequences of the Deepwater Horizon oil spill on pelagic cetaceans Open

Tiago A. Marques, Len Thomas, Cormac Booth, LP Garrison, Patricia E. Rosel , et al. · 2023

The Deepwater Horizon disaster resulted in the release of 490000 m 3 of oil into the northern Gulf of Mexico. We quantified population consequences for pelagic cetaceans, including sperm whales, beaked whales and 11 species of delphinids. …

Flexible hidden Markov models for behaviour-dependent habitat selection Open

Natasha J. Klappstein, Len Thomas, Théo Michelot · 2023

Designing line transect surveys for complex survey regions Open

Len Thomas, Robert W. Williams, Doug Sandilands · 2023

Line transect surveys are widely used to estimate the density and/or size of cetacean populations. Good survey design is essential for obtaining reliable results using standard (design-based) analysis methods. Even for more complex (model-…

Distribution and abundance of marine mammals in the coastal waters of British Columbia, Canada Open

Rob Williams, Len Thomas · 2023

Information on animal distribution and abundance is integral to wildlife conservation and management. However abundance estimates have not been available for many cetacean species inhabiting the coastal waters of Canada’s Pacific coast, in…

An expert‐based system to predict population survival rate from health data Open

Lori H. Schwacke, Len Thomas, Randall S. Wells, Teresa K. Rowles, Gregory D. Bossart , et al. · 2023

Timely detection and understanding of causes for population decline are essential for effective wildlife management and conservation. Assessing trends in population size has been the standard approach, but we propose that monitoring popula…

Estimating the effects of stressors on the health, survival and reproduction of a critically endangered, long‐lived species Open

Enrico Pirotta, Robert S. Schick, Philip K. Hamilton, Catriona M. Harris, Joshua Hewitt , et al. · 2023

Quantifying the cumulative effects of stressors on individuals and populations can inform the development of effective management and conservation strategies. We developed a Bayesian state–space model to assess the effects of multiple stre…

Continuous-time modelling of behavioural responses in animal movement Open

Théo Michelot, Richard Glennie, Len Thomas, Nicola J. Quick, Catriona M. Harris · 2022

There is great interest in ecology to understand how wild animals are affected by anthropogenic disturbances, such as sounds. Behavioural response studies are an important approach to quantify the impact of naval activity on marine mammals…

Flexible hidden Markov models for behaviour-dependent habitat selection Open

Natasha J. Klappstein, Len Thomas, Théo Michelot · 2022

There is strong incentive to model behaviour-dependent habitat selection, as this can help delineate critical habitats for important life processes and reduce bias in model parameters. For this purpose, a two-stage modelling approach is of…

Managing the effects of multiple stressors on wildlife populations in their ecosystems: developing a cumulative risk approach Open

Peter L. Tyack, Len Thomas, Daniel P. Costa, A. Hall, Catriona M. Harris , et al. · 2022

Assessing cumulative effects of human activities on ecosystems is required by many jurisdictions, but current science cannot meet regulatory demands. Regulations define them as effect(s) of one human action combined with other actions. Her…

More vaquita porpoises survive than expected Open

Lorenzo Rojas‐Bracho, Barbara L. Taylor, Cormac Booth, Len Thomas, Armando M. Jaramillo‐Legorreta , et al. · 2022

In 2018, it was estimated that fewer than 20 of Mexico’s endemic vaquita porpoise Phocoena sinus remained, and the species was declining by 47% yr -1 . Entanglement in gillnets is the sole threat to the species, and since the last populati…

Accommodating false positives within acoustic spatial capture-recapture, with variable source levels, noisy bearings and an inhomogeneous spatial density Open

Felix T. Petersma, Len Thomas, Aaron M. Thode, Danielle Harris, Tiago A. Marques , et al. · 2022

Passive acoustic monitoring is a promising method for surveying wildlife populations that are easier to detect acoustically than visually. When animal vocalisations can be uniquely identified on an array of sensors, the potential exists to…

Quantifying the response of Blainville's beaked whales to U.S. naval sonar exercises in Hawaii Open

Eiren K. Jacobson, E. Elizabeth Henderson, David L. Miller, C. S. Oedekoven, David Moretti , et al. · 2022

Behavioral responses of beaked whales (family Ziphiidae) to naval use of mid‐frequency active sonar (MFAS) have been quantified for some species and regions. We describe the effects of MFAS on the probability of detecting diving groups of …

Model predicts catastrophic decline of common bottlenose dolphin (Tursiops truncatus) population under proposed land restoration project in Barataria Bay, Louisiana, USA Open

Len Thomas, Tiago A. Marques, Cormac Booth, Ryan Takeshita, Lori H. Schwacke · 2022

The Barataria Bay Estuarine System (BBES) Stock is one of 31 identified stocks of common bottlenose dolphin (Tursiops truncatus) occupying the bays, sounds, and estuaries of the northern Gulf of Mexico (NOAA, 2019). The stock (hereafter “d…

Estimating the abundance of the critically endangered Baltic Proper harbour porpoise (Phocoena phocoena) population using passive acoustic monitoring Open

Mats Amundin, Julia Carlström, Len Thomas, Ida Carlén, Jens C. Koblitz , et al. · 2022

Knowing the abundance of a population is a crucial component to assess its conservation status and develop effective conservation plans. For most cetaceans, abundance estimation is difficult given their cryptic and mobile nature, especiall…

Len Thomas YOU? Author Swipe