Search results for "OVEREXPLOITATION"

Throwing down a genomic gauntlet on fisheries-induced evolution

2021

Beginning with studies on crypsis and camouflage, the hypothesis that predators can generate evolutionary change in their prey has a long and rich history (1). Few predators, however, rival humans in their potential to generate selection responses and concomitant phenotypic change on contemporary timescales. In the 1930s, J. B. S. Haldane (2) mused that fishing would be an ideal candidate for such “observable evolution” within a human lifetime, proceeding “with extreme and abnormal speed.” However, it was not until the late 1970s that research on fisheries-induced evolution (FIE) gained a substantive scientific foothold, beginning with thought-provoking work on Canadian whitefish ( Coregonu…

2021

Abstract Despite islands contributing only 6.7% of land surface area, they harbor ~20% of the Earth’s biodiversity, but unfortunately also ~50% of the threatened species and 75% of the known extinctions since the European expansion around the globe. Due to their geological and geographic history and characteristics, islands act simultaneously as cradles of evolutionary diversity and museums of formerly widespread lineages—elements that permit islands to achieve an outstanding endemicity. Nevertheless, the majority of these endemic species are inherently vulnerable due to genetic and demographic factors linked with the way islands are colonized. Here, we stress the great variation of islands…

Phycological Herbaria as a Useful Tool to Monitor Long-Term Changes of Macroalgae Diversity: Some Case Studies from the Mediterranean Sea

2020

The Mediterranean Sea is currently experiencing a decline in the abundance of several key species, as a consequence of anthropogenic pressures (e.g., increase in human population, habitat modification and loss, pollution, coastal urbanization, overexploitation, introduction of non-indigenous species and climate change). Herbaria and natural history collections are certainly fundamental for taxonomic studies, but they are also an invaluable, if currently underestimated, resource for understanding ecological and evolutionary responses of species to environmental changes. Macroalgae herbarium collections, which are really consistent (ranging from 200,000 to approximately 500,000 specimens) in …

Potential of contemporary evolution to erode fishery benefits from marine reserves

2016

Marine reserves are valued for their ecological role: protecting fish populations from overharvesting while, at the same time, potentially maintaining fisheries yields via recruitment effects (net export of pelagic eggs and larvae) and spillover (net export of post-settled juveniles and mature fish) across reserve borders. Focussing on the spillover effect, we argue that when fitness of the protected individuals depends on the relative size of their home ranges compared to the reserve size, and home range size is a property of the individuals, rapid local adaptation might occur in favour of individuals with smaller home ranges. Individuals that avoid fishing mortality by spending most of th…

Harvest‐induced evolution and effective population size

2016

Much has been written about fishery-induced evolution (FIE) in exploited species, but relatively little attention has been paid to the consequences for one of the most important parameters in evolutionary biology-effective population size (N-e). We use a combination of simulations of Atlantic cod populations experiencing harvest, artificial manipulation of cod life tables, and analytical methods to explore how adding harvest to natural mortality affects N-e, census size (N), and the ratio N-e/N. We show that harvest-mediated reductions in N-e are due entirely to reductions in recruitment, because increasing adult mortality actually increases the N-e/N ratio. This means that proportional red…

The effects of marine protected areas on ecosystem recovery and fisheries using a comparative modelling approach

2020

17 pages, 11 figures, 1 table, supporting information https://doi.org/10.1002/aqc.3368.-- This is the peer reviewed version of the following article: Daniel Vilas, Marta Coll, Xavier Corrales, Jeroen Steenbeek, Chiara Piroddi, Antonio Calò, Antonio Di Franco, Toni Font, Paolo Guidetti, Alessandro Ligas, Josep Lloret, Giulia Prato, Rita Sahyoun, Paolo Sartor, Joachim Claudet, The effects of marine protected areas on ecosystem recovery and fisheries using a comparative modelling approach, Aquatic Conservation - Marine and Freshwater Ecosystems 30(10):1885-1901(2020), which has been published in final form at https://doi.org/10.1002/aqc.3368. This article may be used for non-commercial purpose…

Measuring the effects of temperature rise on Mediterranean shellfish aquaculture

2018

Abstract Shellfish aquaculture represents a worldwide valuable segment of the aquaculture market, spreading along the Mediterranean coasts, and is sensitive to the still unforeseen, poorly-known effects of climate change. Threats due to temperature rise can threaten the deployment and development of this sector, up until now recognised as the best candidate to mitigate the effects of fishery overexploitation. Here, we investigate the effects of temperature increase on the model species, Mytilus galloprovincialis, measuring outcomes from valve fragility (thickness) and condition index. Evidence of a reduction in the thickness of valves and the modulation condition of the mussels along with t…

Characteristics, Main Impacts, and Stewardship of Natural and Artificial Freshwater Environments: Consequences for Biodiversity Conservation

2020

International audience; In this overview (introductory article to a special issue including 14 papers), we consider all main types of natural and artificial inland freshwater habitas (fwh). For each type, we identify the main biodiversity patterns and ecological features, human impacts on the system and environmental issues, and discuss ways to use this information to improve stewardship. Examples of selected key biodiversity/ecological features (habitat type): narrow endemics, sensitive (groundwater and GDEs); crenobionts, LIHRes (springs); unidirectional flow, nutrient spiraling (streams); naturally turbid, floodplains, large-bodied species (large rivers); depth-variation in benthic commu…

A case study of the coconut crab Birgus latro on Zanzibar highlights global threats and conservation solutions

2021

Abstract The coconut crab Birgus latro, the largest terrestrial decapod, is under threat in most parts of its geographical range. Its life cycle involves two biomes (restricted terrestrial habitats near the coast, and salt water currents of the tropical Indian and Pacific Oceans). Its dependence on coastal habitat means it is highly vulnerable to the habitat destruction that typically accompanies human population expansion along coastlines. Additionally, it has a slow reproductive rate and can reach large adult body sizes that, together with its slow movement when on land, make it highly susceptible to overharvesting. We studied the distribution and population changes of coconut crabs at 15…

Exotic Meats: An Alternative Food Source

2019

International audience; Exotic meats were a protein source for human diet for many years. However, the massive capture caused the overexploitation and placed many reptiles and amphibious on the verge of extinction. Therefore, the captive rearing, the control during slaughtering and processing has been proposed as an alternative to the capture of wild animals. The present chapter shows the nutritional composition of this kind of meat, characterized by low levels of fat, high contents of protein, essential amino acids, fatty acids (especially long-chain n-3) and minerals indicating that their consumption may be beneficial for human health. However, very little data is available on the nutriti…