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Climate Attribution in Fishery Stock Assessment: Case Studies From the Northeast U.S. Groundfish StocksNARA Subscribed
Climate change poses an unprecedented risk to fisheries ecosystems and economies globally. Ocean warming has led to observed geographic shifts and changes in the productivity of fish stocks. Due to the rapid pace of change in many of the world's oceans, there is a critical need to develop and apply scientific knowledge and tools that can help account for non‐stationarity and integrate climate and ecosystem drivers into fishery...
Benthic primary producers affect pelagic nitrogen fixation by influencing benthic nutrient fluxes in a shallow lakeNARA Subscribed
Nutrient supply is an important determinant of N fixation rates in pelagic cyanobacteria. In shallow aquatic ecosystems, benthic primary producers can affect nutrient release from the sediment to the pelagic zone, yet the relationship between benthic primary producers and pelagic N fixation is not well understood. Here, we explore the effect of benthic primary producers on benthic nutrient fluxes and pelagic N fixation rates i...
In nitrogen-limited lakes, cyanobacterial nitrogen (N) fixation rates can be high. However, the effect of cyanobacterial N fixation on ecosystem N availability depends, in part, on the retention of fixed N. Here, we explore patterns of benthic and pelagic N fixation and fixed N retention in Lake Mývatn, Iceland. Our N budget, updated from previous assessments, showed that the annual rate of lake-scale N fixation needed to acco...
Under the current global biodiversity crisis, there is a need for automated and noninvasive monitoring techniques that can gather large amounts of data cost‐effectively at various ecological scales, from local to large spatial scales. These data can then be analyzed to inform stakeholders and decision‐makers. One such technique is passive acoustic monitoring, which is commonly coupled with automatic identification of animal sp...
In recent years, there has been an increasing need for climate information across diverse sectors of society. This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and change. Likewise, this period has seen a significant increase in our understanding of the physical processes and mechanisms that drive precipitation and its variability across different regions of Africa. By levera...
Age-related Changes in Dehydroepiandrosterone-sulfate in Black-and-gold Howler Monkeys (Alouatta caraya)NARA Subscribed
Dehydroepiandrosterone-sulfate (DHEAS) is the most abundant steroid in humans and some nonhuman primates. This adrenal androgen contributes to immune enhancement, neuroprotection, and reproduction. In humans and apes, DHEAS levels increase before puberty, a phenomenon called adrenarche. However, a postnatal increase in the levels of these hormones is not apparent in cercopithecoids. In marmosets, DHEAS is only synthesized from...
Ecosystem Changes Caused by Hydrological Change are Associated with Population Decline in a Formerly-Common Grazing HerbivoreNARA Subscribed
Few ecosystems are more sensitive to hydrological change than seasonally-flooded wetlands. Here, we investigate how changes in hydrological regimes caused by the construction of two dams have contributed to large changes in the structure and dynamics of the Kafue Flats, an internationally-important, partially-protected wetland ecosystem in Zambia. We use historical (1970) and contemporary (2013) data to describe changes in hyd...
Defining an ageing-related pathology, disease or syndrome: International Consensus StatementNARA Subscribed
Around the world, individuals are living longer, but an increased average lifespan does not always equate to an increased health span. With advancing age, the increased prevalence of ageing-related diseases can have a significant impact on health status, functional capacity and quality of life. It is therefore vital to develop comprehensive classification and staging systems for ageing-related pathologies, diseases and syndrom...
A quasi-geostrophic analysis of summertime southern African linear-regime westerly wavesNARA Subscribed
Linear-regime westerly waves that propagate across the South African domain are often linked to well-known rainfall producing systems such as tropical temperate troughs and synoptic scale tropical low-pressure systems, and ridging South Atlantic Ocean anticyclones at the surface. It is accepted that the baroclinic waves that propagate across the domain provide the lifting mechanism that causes the required vertical motion for...
Adaptation of sea turtles to climate warming: Will phenological responses be sufficient to counteract changes in reproductive output?NARA Subscribed
Sea turtles are vulnerable to climate change since their reproductive output is influenced by incubating temperatures, with warmer temperatures causing lower hatching success and increased feminization of embryos. Their ability to cope with projected increases in ambient temperatures will depend on their capacity to adapt to shifts in climatic regimes. Here, we assessed the extent to which phenological shifts could mitigate im...
Assessing the linkage between breeding and non-breeding areas has important implications for understanding the fundamental biology of and conserving animal species. This is a challenging task for marine species, and in sea turtles a combination of stable isotope analysis (SIA) and satellite telemetry has been increasingly used. The Northwest Atlantic (NWA) loggerhead ( Caretta caretta ) Regional Management Unit, one of the lar...
Marine protected areas (MPAs), particularly large MPAs, are increasing in number and size around the globe in part to facilitate the conservation of marine megafauna under the assumption that large-scale MPAs better align with vagile life histories; however, this alignment is not well established. Using a global tracking dataset from 36 species across five taxa, chosen to reflect the span of home range size in highly mobile ma...
Phthalates are endocrine-disrupting chemicals added to plastics, personal care products, cleaning solutions, and pesticides. Extensive use has led to its exposure to wildlife, including common bottlenose dolphins (Tursiops truncatus) from Sarasota Bay, Florida, USA; however, there are gaps in knowledge regarding whether sample timing or geographic location influence exposure. Dolphins were evaluated for temporal and spatial va...