ABSTRACT. This study used transcriptomics tracers and measurements of oxidative stress to examine the effect of capture by longline on the silky shark Carcharhinus falciformis. From February 2010 to May 2012, C. falciformis individuals captured in the eastern Pacific Ocean were initially examined for sex, degree of maturity, and morphometric data. Samples were then taken from muscle tissue to determine RNA, DNA, and protein concentrations as well as RNA/DNA and protein/DNA ratios. The levels of three oxidative stress indicators [superoxide dismutase (SOD), glutathione (GSH), and malondialdehyde (MDA)] were determined in muscle. The analysis of the 159 specimens (93 juveniles and 66 adults) showed low RNA/DNA ratios at the different stages of maturity. This basal level of transcriptomics capacity may have been caused by the physiological stress resulting from capture. In juveniles, the low RNA/DNA and protein/DNA ratios were associated with low levels of cellular damage related to oxidative stress, whereas in adults the level of cell damage due to oxidative stress was high, especially in older females. This pattern indicated decreased antioxidant response capacity with increasing age in elasmobranchs.
The present study originated with the expansion of the boardwalk within the urban and port area of Manzanillo, México. Prior to civil works related to the placement of tetrapods, surveys of potential sites for the relocation of benthic organisms in alternative areas were carried out.
Based on indicators of the physical–chemical environment and biotic factors, nine areas with potential for relocation were evaluated. The areas of greatest potential were associated with environments located away from the influence of the port environment.
A total of 13,559 benthic organisms belonging to 68 species associated with three main substratum types (rocky, sandy, and mixed) were collected. There were no differences in the ecological indices between the three substrata.
The proximity of the collection area to the influence of port traffic and sources of pollution associated with the physical environment could be an important factor that affects ecological indices and the reduction in the abundance of some protected species and species of commercial interest.
The success of collection and relocation processes depends on minimizing possible errors, especially during transportation, when overcrowding, handling, and damage resulting from variable physico‐chemical conditions should be avoided.
Through a scheme of actions based on ecological principles, management actions, and civil engineering technology, it was possible to carry out mitigation, conservation, and habitat improvement actions in coastal marine environments exposed to anthropogenic impacts.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.