Several reproductive issues and the larval development of the ferruginous limpet, Patella ferruginea Gmelin, 1791, an endangered species endemic from the western Mediterranean Sea, were studied to fill gaps in the knowledge of its life cycle.Average diameter of mature oocytes was 141.83 μm and mean oocyte density in the ovary was 283,800 oocytes/gram. No significant correlations were found between both oocyte diameter or density and female shell length. Female fecundity (number of oocytes per gonad) was significantly correlated with shell length and varied between 189,200 oocytes in a 40.0 mm female and 5,019,200 oocytes in an 86.4 mm female. However, there was considerable variability, in particular for largest females.Spawning induction was not achieved using usual molluscan aquaculture methods. Thus, oocytes obtained after dissection of females were used for fertilizations trials. Alkalinization treatments of seawater were used to test improvement in oocyte maturation and later fertilization rates. Treatment at pH 9 during 2 h produced the highest increase in the percentage of mature oocytes and in the fertilization rate; but these results showed high variability and were mainly significant when the initial degree of maturation was low. Sperm concentration experiments determined that best in vitro fertilization were performed at 105 and 5×105 spermatozoids/ml. The sequence and timing of the complete larval development of Patella ferruginea in laboratory conditions is described and illustrated here for the first time. At 20 °C, larvae became competent for metamorphosis 3 days after fertilization, but some crawling pediveliger larvae with a still well developed velum were found even 7 days after fertilization. Recruits 1-2 mm in length were achieved in low numbers from two of the last assays and were first detected between 131-141 days after fertilization. The resulting juveniles were monitored during two years and sex determination of five survivors at the end of this period showed that two were mature males, two mature females and one indeterminate.Our results show that the main reproductive traits or larval development of P. ferruginea hardly differ from those of other non-endangered Mediterranean or NE Atlantic limpet species. Therefore, its decline cannot be mainly attributed to some constraints of these traits as was previously suggested, but to human impact.On the other hand, it is feasible to complete the life cycle of this species in laboratory conditions, from fertilized eggs to mature individuals. However, an important part of the process like spawning induction was not achieved as gonads needed to be dissected fatally from females, although sperm could be obtained from males through non-lethal biopsies. At present, large-scale aquaculture production for reintroduction, restocking or stock enhancement purposes is neither possible nor an advisable conservation tool yet. Further study is required and meanwhile, an appropriate design of a network of effectively protected marine areas that ensures connectivity among extant populations is necessary.

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Unintended mortality in longlines emerged in the early 1990s as one of the most important threats for pelagic seabirds worldwide. Most of the studies were focused on highly developed industrial fisheries, overlooking bycatch in small-scale artisanal fisheries. However, bycatch in smallscale fisheries might have negative effects similar to those of industrial fisheries when they overlap with hotspot areas of top predators. Moreover, different types of fishing gear coexist in the same oceanographic area, particularly in highly exploited marine ecosystems such as the western Mediterranean. We quantify for the first time the influence of trawling regime on Cory's shearwater Calonectris diomedea bycatch in the western Mediterranean longline artisanal fishery. The availability of trawling discards has substantial influence on the foraging and breeding ecology of many seabirds, and trawling inactivity may drive shearwaters to seek alternative food resources, such as baits used in longline fishing. Based on our previous knowledge of the system, we also tested other variables affecting bycatch over 8 yr (1998 to 2005). Within this 2-fishery framework, we found that trawling regime, longline fishing time and breeding stage were key factors explaining shearwater attendance to longline vessels, but mainly trawling regime and fishing time increased the incidental capture of Cory's shearwaters. More specifically, during the pre-breeding and chick-rearing periods, bycatch dramatically increased during sunrise sets in the absence of trawling activity. Importantly, this study indicates the need for an integrated multi-fisheries management approach for the conservation of seabirds and highlights the necessity of banning longline fishing during periods of trawling inactivity.KEY WORDS: Small-scale fishery · Interactions between fisheries · Multi-fisheries management · Trawling inactivity · Cory's shearwater · Mitigation measures · Western Mediterranean Resale or republication not permitted without written consent of the publisherMar Ecol Prog Ser 420: [241][242][243][244][245][246][247][248][249][250][251][252] 2010 for an 80% reduction in community biomass, affecting both target and non-target species (Myers & Worm 2003, Lewison et al. 2004b). For instance, many thousands of seabirds (mostly Procellariiformes) are killed annually by longline fisheries, and consequently populations have shown important declines in abundance over the last 3 to 4 decades (Weimerskirch & Jouventin 1987, Gales et al. 1998, Brothers et al. 1999, Nel et al. 2002, Cooper et al. 2003. In fact, one-third of the seabird species accidentally caught are catalogued as globally threatened according to the International Union for Conservation of Nature (IUCN) criteria (Brothers et al. 1999, BirdLife International 2004.Most studies reporting top predator bycatch have been performed on highly developed industrial fisheries, and it has seldom been considered in small-scale artisanal fisheries (but see D'Agrosa et al. 2000, Peckham et al. 2007, Bugoni e...

The gulper sharks (genus Centrophorus) are a group of deep-water benthopelagic sharks with a worldwide distribution. The alpha taxonomy of the group has historically been problematic and the number of species included in the genus has varied considerably over the years and is still under debate. Gulper sharks are routinely caught in mid-and deep-water fisheries worldwide and some have shown a considerable decline in abundance in the last few decades. Clear and consistent species discrimination of Centrophorus is essential for an efficient and sustainable management of these fisheries resources. Our study used molecular cytochrome oxidase subunit I (COI) and 16S ribosomal RNA gene sequences] and morphometric data to re-evaluate the diversity of Centrophorus in North Atlantic waters, including the Gulf of Mexico, the Caribbean, and the Mediterranean Seas. Molecular data separated North Atlantic Centrophorus into five well-supported groups whereas morphometric data separated these same five groups and suggested three additional groups for which no molecular data were available. Four of the five groups identified in the North Atlantic also occur in the Indian and/or Pacific Oceans, thus extending the reported range of some species considerably. A species identification key for North Atlantic Centrophorus is provided based on our findings.

The ferruginous limpet is one of the most threatened invertebrate species in the Mediterranean Sea. Its controlled reproduction has been considered one of the potentially most effective strategies for the production of juveniles for population restocking or for recolonization of areas where the species was brought to extinction by human pressure but is now under protection (e.g., MPAs). This approach has been pursued for at least two decades but with partial results: at most, some juveniles have been obtained and have reached adult stage, yet not starting from spawning induction but through sacrifice of female specimens (lethal approach), additionally resulting in low genetic diversity of the juveniles produced. Herein, we describe, for the first time, positive results of the spawning induction in P. ferruginea. The fertilizations made after these experiences allow describing the larval development of the species from its early stages to its metamorphosis. The fertilization rate in these spawning events was much higher (>97%) than in previous studies that were based on the extraction of oocytes by dissection. The rate of non-anomalous larvae after 15 hours was not negligible but variable, depending perhaps on the quality of the sperm available at each fertilization. The timing of larval development of the species and its variability, particularly regarding metamorphosis, are described. Settlement ability is reached at 3-4 days after fertilization, depending on water temperature, while a large variability is observed in metamorphosis, occurring between 7 and 32 days (probably up to 40 days), although inducing factors are still unknown.