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SNAPSHOT USA 2024: Year 6 of the Coordinated National Camera Trap Survey of the United StatesNARA Subscribed
Motivation SNAPSHOT USA is an annual, multi‐contributor camera trap survey of mammals across the United States. The growing SNAPSHOT USA dataset is intended for tracking the spatial and temporal responses of mammal populations to changes in land use, land cover and climate. These data will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, as well as the impacts of speci...
Marine megafauna species are affected by a wide range of anthropogenic threats. To evaluate the risk of such threats, species’ vulnerability to each threat must first be determined. We build on the existing threats classification scheme and ranking system of the International Union for Conservation of Nature (IUCN) Red List of Threatened Species by assessing the vulnerability of 256 marine megafauna species to 23 at‐sea threat...
Materials currently used to produce reef structures are often limited by high production costs, negative environmental impacts or limited flexibility in design and degradability. We tested the ability of a novel concrete alternative, Xiriton, to i) exhibit adjustable erodibility using different mixtures, ii) limit the input of foreign products into the marine environment by using locally sourced building materials (e.g. local...
The effect of a climatic compound drought and heatwave event on the dune-building grass Elytrigia junceaNARA Subscribed
Background and aims Coastal dunes provide vital ecosystem services, including flood protection and freshwater storage. These ecosystems are shaped by clonally-growing dune grasses that trap sediment as patch size increases, enabling the grasses to avoid stress from seawater flooding and freshwater scarcity. However, it remains poorly understood how increasing climate extremes will impact the establishment and survival dynamics...
SNAPSHOT USA 2019–2023: The First Five Years of Data From a Coordinated Camera Trap Survey of the United StatesNARA Subscribed
Motivation SNAPSHOT USA is an annual, multicontributor camera trap survey of mammals across the United States. The growing SNAPSHOT USA dataset is intended for tracking the spatial and temporal responses of mammal populations to changes in land use, land cover and climate. These data will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, as well as the impacts of specie...
Narwhal abundance in West Greenland (WG) and East Greenland (EG) was estimated from aerial surveys conducted between 2007 and 2019 at their summer grounds. Analyses were completed using Mark Recapture Distance Sampling and Hidden Markov Line Transect Models taking account of the stochastic availability of diving whales. No statistically significant difference in abundance of narwhals could be detected for the two summer ground...
Population genomics of the muskox' resilience in the near absence of genetic variationNARA Subscribed
Genomic studies of species threatened by extinction are providing crucial information about evolutionary mechanisms and genetic consequences of population declines and bottlenecks. However, to understand how species avoid the extinction vortex, insights can be drawn by studying species that thrive despite past declines. Here, we studied the population genomics of the muskox ( Ovibos moschatus ), an Ice Age relict that was at t...
One of the last pristine marine soundscapes, the Arctic, is exposed to increasing anthropogenic activities due to climate-induced decrease in sea ice coverage. In this study, we combined movement and behavioral data from animal-borne tags in a controlled sound exposure study to describe the reactions of narwhals, Monodon monoceros , to airgun pulses and ship noise. Sixteen narwhals were live captured and instrumented with sate...
Circumpolar phylogeography and demographic history of beluga whales reflect past climatic fluctuationsNARA Subscribed
Several Arctic marine mammal species are predicted to be negatively impacted by rapid sea ice loss associated with ongoing ocean warming. However, consequences for Arctic whales remain uncertain. To investigate how Arctic whales responded to past climatic fluctuations, we analysed 206 mitochondrial genomes from beluga whales ( Delphinapterus leucas ) sampled across their circumpolar range, and four nuclear genomes, covering bo...
From 25 to 30 August 2014 a double‐observer line‐transect survey was conducted over Melville Bay, home to one of two summering populations of narwhal ( Monodon monoceros ) off West Greenland. A total of 1,932 linear kilometers was surveyed along 33 transects. In addition to using observers, the aircraft was equipped with two oblique cameras to capture a comparable data set. Analysts reviewed the images for narwhal sightings, w...
Spatial self‐organized patterning in seagrasses along a depth gradient of an intertidal ecosystemNARA Subscribed
The spatial structure of seagrass landscapes is typically ascribed to the direct influence of physical factors such as hydrodynamics, light, and sediment transport. We studied regularly interspaced banded patterns, formed by elongated patches of seagrass, in a small‐scale intertidal ecosystem. We investigated (1) whether the observed spatial patterns may arise from feedback interactions between seagrass and its abiotic environ...
The worldwide observed dramatic decline of seagrasses has typically been attributed to multiple stressors such as eutrophication, disease, sedimentation, and toxicity events. Using principal component analysis and (multivariate) logistic regression, we investigated the importance of 30 commonly measured variables in explaining the presence and absence of the temperate seagrass species Zostera marina and Zostera noltii at 84 We...
Population structure of long‐finned pilot whales in the North Atlantic: a correlation with sea surface temperature?NARA Subscribed
The long‐finned pilot whale, Globicephala melas , is a social, pelagic odontocete distributed widely in the cold temperate waters of the North Atlantic. Despite genetic, morphometric, physiological and observational studies, it remains unclear whether any population substructure exists. We have used eight highly polymorphic microsatellite loci to analyse samples from four disparate sampling sites: USA East Coast (Cape Cod), We...
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