Juana López-Martínez

INTERANNUAL VARIABILITY OF THE REPRODUCTIVE PERIOD OF THE BROWN SHRIMP, FARFANTEPENAEUS CALIFORNIENSIS (HOLMES, 1900) (DECAPODA, NATANTIA)

[Interannual changes in the reproductive pattern of the brown shrimp, Farfantepenaeus californiensis, a commercially important marine crustacean, were analysed as a function of sea water temperature. Daily samples of gravid females from 1979 through 1994 and monthly sea water temperatures were examined. The results show a high interannual variability of the reproductive period with two patterns; one in which spawning occurs throughout the year, the other with two peaks of mass spawning. The first of the two peaks is the more intense, occurring from March to May; the other is in October and November and is less intense. The extended spawning period occurs under warmer conditions and is probably associated with El Nino events. The pattern with two peaks is associated with average sea water temperatures. Occurrence of one pattern or the other may have significant consequences for managing this fishery. Los cambios interanuales en el patron reproductivo del camaron cafe Farfantepenaeus californiensis, un crustaceo escencialmente marino, fueron analizados en funcion de la temperatura del agua de mar. Se analizaron muestreos diarios de hembras ovigeras y temperatura promedio mensual del agua de mar desde 1979 a 1994. Los resultados muestran, una alta variabilidad interanual del periodo reproductivo con dos patrones: uno en el que el desove se efectua a todo lo largo del ano y otro con dos periodos masivos de reproduccion. El primero de ellos siendo el mas intenso y presentandose durante marzo a mayo, el segundo es menos intenso y ocurre de octubre a noviembre. La extension del periodo reproductivo ocurre cuando se presentan condiciones calidas y es probable que este asociado a eventos El Nino. El patron con dos periodos de reproduccion masiva se observo principalmente bajo condiciones promedio. La ocurrencia de uno y otro patron puede tener consecuencias importantes para el manejo de la pesqueria., Interannual changes in the reproductive pattern of the brown shrimp, Farfantepenaeus californiensis, a commercially important marine crustacean, were analysed as a function of sea water temperature. Daily samples of gravid females from 1979 through 1994 and monthly sea water temperatures were examined. The results show a high interannual variability of the reproductive period with two patterns; one in which spawning occurs throughout the year, the other with two peaks of mass spawning. The first of the two peaks is the more intense, occurring from March to May; the other is in October and November and is less intense. The extended spawning period occurs under warmer conditions and is probably associated with El Nino events. The pattern with two peaks is associated with average sea water temperatures. Occurrence of one pattern or the other may have significant consequences for managing this fishery. Los cambios interanuales en el patron reproductivo del camaron cafe Farfantepenaeus californiensis, un crustaceo escencialmente marino, fueron analizados en funcion de la temperatura del agua de mar. Se analizaron muestreos diarios de hembras ovigeras y temperatura promedio mensual del agua de mar desde 1979 a 1994. Los resultados muestran, una alta variabilidad interanual del periodo reproductivo con dos patrones: uno en el que el desove se efectua a todo lo largo del ano y otro con dos periodos masivos de reproduccion. El primero de ellos siendo el mas intenso y presentandose durante marzo a mayo, el segundo es menos intenso y ocurre de octubre a noviembre. La extension del periodo reproductivo ocurre cuando se presentan condiciones calidas y es probable que este asociado a eventos El Nino. El patron con dos periodos de reproduccion masiva se observo principalmente bajo condiciones promedio. La ocurrencia de uno y otro patron puede tener consecuencias importantes para el manejo de la pesqueria.]

Interannual variation of growth of the brown shrimp Farfantepenaeus californiensis and its relation to temperature

Abstract We evaluated the interannual variation in the growth of brown shrimp Farfantepenaeus californiensis and the relation of this variation with sea surface temperature in the Gulf of California, Mexico. We used daily samplings of commercial captures at the packing plant at Guaymas, Sonora, Mexico from 1978 to 1994, samplings of commercial captures on board trawlers of the commercial fleet that operated along the coast of Sonora during the fishing seasons 1989–1995, and the monthly average of the sea surface temperature recorded by the oceanographic station of the Institute of Geophysics of the National University of Mexico, in Guaymas, Sonora from 1978 to 1995. The growth in the brown shrimp showed clear interannual variations. The relation between the temperature and the φ′and temperature and the growth coefficient K could be represented by a gaussian function that was significant (P

Jellyfish fisheries in the Americas: origin, state of the art, and perspectives on new fishing grounds

Jellyfish (primarily scyphomedusae) fisheries have a long history in Asia, where jellyfish have been caught and processed as food for centuries. More recently, jellyfish fisheries have expanded to the Western Hemisphere, often driven by demand from Asian buyers and collapses of more traditional local fish stocks. Jellyfish fisheries have been attempted in numerous countries in North, Central, and South America, with varying degrees of success. Here, we chronicle the arrival of jellyfish fisheries in the Americas and summarize relevant information on jellyfish fishing, processing, and management. Processing technology for edible jellyfish has not advanced, and presents major concerns for environmental and human health. The development of alternative processing technologies would help to eliminate these concerns and may open up new opportunities for markets and species. We also examine the biodiversity of jellyfish species that are targeted for fisheries in the Americas. Establishment of new jellyfish fisheries appears possible, but requires a specific combination of factors including high abundances of particular species, processing knowledge dictated by the target market, and either inexpensive labor or industrialized processing facilities. More often than not, these factors are not altogether evaluated prior to attempting a new jellyfish fishery. As such, jellyfish fisheries are currently expanding much more rapidly than research on the subject, thereby putting ecosystems and stakeholders’ livelihoods at risk.

Fish assemblages in the bycatch of bottom shrimp trawls on the west side of the Gulf of California, Mexico

Abstract The assemblage of the fish species obtained as bycatch in trawl nets on the Gulf of California in 2004, 2005 and 2007 was studied. Sampling was carried out during July and August at a series of stations along the coast of Sonora. The criteria for the most important fish species caught were drawn from abundance and frequency of occurrence and weight, using various ecological indices (index of relative abundance, biological value index and index of relative importance). After identification, these species and their abundances were used to define study groups based on similarity matrices and Wards clustering method. We analysed 125 fish hauls containing>19,000 organisms, representing 243 species (fish, crustaceans, molluscs and echinoderms). There were 28 dominant species, most notably Urobatis halleri, Synodus scituliceps, Eucinostomus argenteus, Diplectrum pacificum and Haemulopsis nitidus. Cluster analysis, based on latitude, and bathymetry showed three station groupings. The first was characterized by species from the northern region of the Gulf with a bathymetric distribution>25 m. The second was dominated by species from the central to southern region from depths<25 m. The third was a transitional group with species found between the central and southern Gulf from depths of 10 to 45 m. Most fish assemblages consist of species with wide distribution within distinct biogeographic provinces, which showed a major change in the association, frequency and absence of species from north to south, indicating a variety of habitats in the Gulf of California.

Trophic spectrum and feeding pattern of cannonball jellyfish Stomolophus meleagris (Agassiz, 1862) from central Gulf of California

The diet and feeding pattern of scyphomedusa Stomolophus meleagris (Rhizostomeae) was studied, by comparing stomach samples from different developmental stages and environmental zooplankton with the aim to determine diet composition, trophic niche breadth, selectivity and feeding overlap of this edible jellyfish species. Samplings were performed during April and December 2010 and in January 2011, in the coastal lagoon Las Guasimas (27°49′–27°54′N 110°40′–110°35′W), central Gulf of California, which consisted of zooplankton tows and jellyfish collections for stomach content. More than 39 prey items were identified in the gut contents (N = 69), from which eight taxa formed over 90% of the total. Fish eggs were considered main prey (58.6%), copepods (10.8%), veliger larvae of gastropod (13.0%) and bivalve (12.7%) were secondary prey while cirriped and decapod larvae were incidental prey ( S. meleagris is a specialist predator and Pearres index showed positive selection of fish eggs, gastropods, bivalves and cirripeds while selectivity was negative for copepods and appendicularians. The relative timing of these changes suggests that ontogenetic processes are closely related with shift in the diet, which indicates increasing predation pressure during development of the medusoid stage of this species, thus emphasizing their ecological importance in coastal ecosystems.

ESTIMATING BIOMASS, RECRUITMENT, AND HARVEST RATE FOR THE PACIFIC YELLOWLEG SHRIMP FARFANTEPENAEUS CALIFORNIENSIS FROM A SIZE-BASED MODEL

ABSTRACT Catch-at-size data were analyzed for Farfantepenaeus californiensis from fishing seasons 1978/1979 to 1994/1995. The catch-at-size model could be fitted to the catch-at-size data for the different fishing seasons. It was observed that the recruitment to the fishery changed suddenly during the study period, and the recruitment to the fishery may occur over a range of length classes. The recruits were defined as size classes less than 93.5mmin abdominal length. Recruitment varied from 200–3,800 million recruits. In contrast, the size classes were larger than 93.5 mm in terms of abdominal length, and the number of adults varied from 3,500,000–50,000,000. In the study zone, it was not common to find remnant biomass of adults. Consequently, the most abundant size intervals of abdominal length were 62.4 mm, 67 mm, and 72.2 mm. The results of the harvest rate-at-size showed that the size interval from 65–80mmin abdominal length was less than 0.05. The highest levels of harvest rate-at-size were estimated to be 85–125mm in abdominal length, with an estimated variation of 0.6–0.9. It was observed that individuals less than 93.5 mm in abdominal length are in the range of length classes in which recruitment to the fishery occurs. These recruits support the fishing pressure and the yield of the fishery; in contrast, the presence of adults is scarce. Therefore, this fishery in the region is strongly recruitment dependent.

Population dynamics of the swimming crabs Callinectes (Portunidae) components of shrimp bycatch in the eastern coast of the Gulf of California

Resumen es: Se reportan por primera vez aspectos de la dinamica poblacional de 3 especies del genero Callinectes: C. arcuatus, C. bellicosus y C. toxotes capturadas ...

Feeding habits of Mustelus henlei on the western coast of Baja California Sur, México

Palabras clave: Contenido estomacal, superposicion de dieta, especialista, Punta Lobos, Baja California Sur, Mexico Abstract.- The Brown smooth-hound Mustelus henlei is part of an important commercial fishery on the western coast of Baja California Sur (BCS), Mexico. However, very few studies have been performed on the feeding and reproduction biology of these sharks in Mexico. Our study is the first work focusing on this species on the western shelf (14 m to 250 m in depth) of B.C.S. We identified a total of 24 types of prey contents in the stomachs of M. henlei: 15 crustaceans, 6 fish, and 3 cephalopods. According to the index of relative importance (IRI) the main prey items for M. henlei was the pelagic red crab Pleuroncodes planipes (81.4%), followed by unidentified organic material (UOM) (15.7%), the mackerel Scomber japonicus (0.94%), and fish remains (0.84%). Conducting a prey analysis considering sex of M. henlei, P. planipes was the most important prey in both females and males, followed by UOM, and S. japonicus. Sharks found in deeper areas (120-150 m) and those caught on board the exploration ship BIP XII had a similar dietary composition to those found in the shallow waters of Punta Lobos (14-40 m) where for both regions, the dominant prey items were the pelagic red crab and UOM. According to Levins index, M. henlei may be a specialist feeder in this area. A diet overlap according to sex, area, and size was observed. The SIMPER analysis showed a low similarity in diet in relation to sex, size, and area. According to the ANOSIM test there were no significant differences. Knowing that M. henlei shows a specialist behavior could help research studies not only for species conservation but also for its habitat and the organisms that inhabit it, which are both of vital importance for this shark.

Environmental Variability and Oceanographic Dynamics of the Central and Southern Coastal Zone of Sonora in the Gulf of California

This study analyzed monthly and inter-annual variability of mesoscale phenomena, including the El Nino Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO) climate indexes and wind intensity considering their influence on sea surface temperature (SST) and chlorophyll a (Chl-a). These analyses were performed to determine the effects, if any, of climate indexes and oceanographic and environmental variability on the central and southern coastal ecosystem of Sonora in the Gulf of California (GC). Monthly satellite images of SST (°C) and Chl-a concentration were used with a 1-km resolution for oceanographic and environmental description, as well as monthly data of the climate indexes and wind intensity from 2002–2015. Significant differences (p > 0.05) were observed while analyzing the monthly variability results of mesoscale phenomena, SST and Chl-a, where the greatest percentage of anti-cyclonic gyres and filaments was correlated with a greater Chl-a concentration in the area of study, low temperatures and, thus, greater productivity. Moreover, the greatest percentage of intrusion was correlated with the increase in temperature and cyclonic gyres and a strong decrease of Chl-a concentration values, causing oligotrophic conditions in the ecosystem and a decrease in upwelling and filament occurrence. As for the analysis of the interannual variability of mesoscales phenomena, SST, Chl-a and winds, the variability between years was not significant (p > 0.05), so no correlation was observed between variabilities or phenomena. The results of the monthly analyses of climate indexes, environmental variables and wind intensity did not show significant differences for the ENSO and PDO indexes (p > 0.05). Nonetheless, an important correlation could be observed between the months of negative anomalies of the ENSO with high Chl-a concentration values and intense winds, as well as with low SST values. The months with positive ENSO anomalies were correlated with high SST values, low Chl-a concentration and moderate winds. Significant inter-annual differences were observed for climate indexes where the years with high SST values were related to the greatest positive anomaly of ENSO, of which 2002 and 2009 stood out, characterized as moderate Nino years, and 2015 as a strong El Nino year. The years with the negative ENSO anomaly were related to the years of lower SST values, of which 2007–2008 and 2010–2011 stood out, characterized as moderate Ninas. Thus, variability associated with mesoscale oceanographic phenomena and seasonal and inter-annual variations of climate indexes had a great influence on the environmental conditions of the coastal ecosystem of Sonora in the Gulf of California.

New depth record of the dappled flounder Paralichthys woolmani (Pleuronectiformes: Paralichthyidae) in the Gulf of California, México

Ten specimens of the dappled flounder Paralichthys woolmani were captured at a depths from 109 to 248.1 m in the central Gulf of California in an exploration cruise on board the research ship BIP XII in February 2005. The average temperature and dissolved oxygen concentration were 14.5°C and 1.01 mg O2 L-1, respectively. P. woolmani had not been reported at greater depth than 100 m. This new record represents an increase of 148.1 m in its bathymetric distribution in the Gulf of California.