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Impact of fisheries on sea turtles

The bycatch of sea turtles by industrial fisheries is receiving an increasing attention in recent years due to the high impact it causes on these endangered species. This issue was evaluated in southern Spain waters that harbors an important feeding ground of loggerhead and leatherback turtles, including the endangered Eastern Atlantic loggerhead population. To quantify the impact that different fisheries represents to sea turtles, 272 fishermen answered to detailed illustrated questionnaires in all the main ports of Andalusia and Murcia (Spain) during 2014. This study has updated the knowledge of turtle bycatch in the southwestern Mediterranean revealing a widespread impact of fisheries on sea turtles. Fishermen recognized an annual catch of 2.3 turtles per boat. Considering the census of industrial fishing boats in the study area (1182), more than 2840 sea turtles could be bycaught per year in the study area. Most of captures (96.2%) were produced during the summer. These results suggest a severe impact of most of legal fisheries (surface longline, pursue seine, trawling and small scale fisheries) on loggerhead feeding grounds in the southwestern Mediterranean. Fishermen suggests that drift fishing conducted by foreign or illegal fishermen and almadrabas are also causing a significant bycatch of turtles. Several measures such as reviewing compliance of current fishing and environmental regulations, modifying turtle technics to reduce turtle bycatch (e.g. reduction of the use of squid as bait and disposal of hooks deeper in the water column), facilitating the rescue and handle of wound turtles and their transport to the port for recovery, and recognizing the efforts of anglers to perform a more sustainable fishing, are recommended to mitigate this impact. informacion[at] Marco et al (2020) Sea turtle bycatch by different types of fisheries in southern Spain. Basic and Applied Herpetology
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Generalized hybridization between commercial and native individuals of bumble bees

Generalized hybridization between commercial and native individuals of bumble bees

Every year more than 1 million commercial bumblebee colonies are deployed in greenhouses worldwide for their pollination services. While commercial pollinators have been an enormous benefit for crop production, their use is emerging as an important threat. Commercial pollinators have been linked to pathogen spillover, and their introduction outside their native area has had devastating effects on native pollinators. A more pervasive but underappreciated threat is their potential impact on the genetic integrity of native pollinators. A sampling and genotyping?plus?phenotyping protocol was set up to evaluate the presence and extent of hybridization between commercial and native individuals of Bombus terrestris in south?western Spain, a region experiencing a huge propagule pressure of non?native genotypes due to the massive use of commercial colonies for crop pollination. Genomic data show clear evidence of generalized hybridization between native and introduced commercial bumblebee lineages in southern Spain. Only 19% of analysed individuals were assigned with high confidence to the pure native genetic cluster and >45% of sampled specimens were first?generation hybrids or backcrosses between native and commercial genotypes, indicating that genetic introgression is pervasive in southern Spain. Although the frequency of commercial genotypes sharply declined with the distance to greenhouses, non?native alleles have introgressed into native populations inhabiting protected natural parks >60 km away from commercial bumblebee release areas. As pollination services demand will increase in the coming years, only a more restrictive regulation of commercial lines could mitigate their negative impacts on the genetic integrity of native pollinators, avoid processes of genetic homogenization, and prevent the potential disruption of local adaptations. informacion[at] Bartomeus et al (2020) Safeguarding the genetic integrity of native pollinators requires stronger regulations on commercial lines. Ecological Solutions and Evidences. Doi 10.1002/2688-8319.12012