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Parasites may influence their hosts in multiple ways, ranging from physiological changes and behavioral modifications, to altering life history traits. One fitness component that is often considered in relation to parasitism is host fecundity. The larval acanthocephalan parasite, Profilicollis altmani, commonly infects the Pacific mole crab, Emerita analoga; yet this parasite's effect on the crab's fecundity is unknown. Consequently, we examined the effects of acanthocephalan parasitism on the fecundity of this mole crab species. Crabs were collected from the swash intertidal zone in Monterey Bay, CA, and the following parameters were quantified: crab body size (carapace length) and weight, egg‐bearing status (nongravid and gravid), egg number and diameter, total volume and weight of egg mass, and their developmental stages (from newly laid eggs to recognizable zoea larval stage). Parasite prevalence, intensity of infection, and body size of larval cystacanths (measured as volume) were assessed. Host fecundity was positively correlated with both body size and body weight. No differences in egg weight were found between uninfected and infected crabs. Similarly, no difference in crab body weight at various embryonic developmental phases was documented between uninfected and infected crabs. Cystacanth volumes in infected nongravid and infected gravid crabs were not significantly different. Our study suggests that the parasite P. altmani does not have any appreciable effect on the fecundity of E. analoga and that female mole crabs undergo normal reproduction and maintain robust population sizes in their natural environments. Our findings thus appear to moderate the pervasive notion of a major impact of parasitism on host reproduction. [ABSTRACT FROM AUTHOR]

California yellowtail (CYT; Seriola dorsalis) is a promising candidate for marine aquaculture in the United States because there is an existing market and cultured Seriola spp. command prices as high as $27.70 per kg for head‐on gutted product. Methods for commercial‐scale Seriola spp. fingerling production and growout have been refined globally in recent years. Spawning can be accomplished without hormone therapy and adults spawn viable eggs when ambient water temperatures are between 15 and 22°C. Larval culture of CYT includes rotifers and Artemia, with the addition of greenwater. Larval survival to 1 g juveniles (45 days post hatch) is typically high at 30–60%. However, poor swim bladder inflation and skeletal malformations require culling and can reduce this yield substantially. Growout of CYT to market size at Hubbs‐SeaWorld Research Institute (HSWRI) has been completed on a very limited basis in flow through tanks where it takes 18–24 months to achieve a market weight of 3.5–4.0 kg. While culture of this species is commercially ready from a technical and business perspective, research is still needed to improve swim bladder inflation, reduce deformities, optimize nutrition across all life stages, and assist with disease diagnosis and control. Most notable among bottlenecks to commercialization in the United States is the need for growout capacity both for net pen and land‐based culture. [ABSTRACT FROM AUTHOR]

The article discusses a study which determined development times, growth rates and fecundity of the small cyclopoid copepod Limnoithona tetraspina from March to August 2006 and 2007. Limnoithona tetraspina was introduced to the San Francisco Estuary (SFE) in California in 1993, which eventually dominated the low-salinity zone (LSZ). Based on low growth and fecundity rates, low mortality played an important role in the population success of Limnoithona tetraspina. The copepod may also avoid some mortality agents.

In California's San Joaquin Valley, feeding by the coreid pest, Leptoglossus zonatus, can cause considerable economic loss on almond and pistachio. This research was conducted to improve understanding of how winter temperatures affect mortality of overwintering adult L. zonatus and to develop a better understanding of the role pomegranate plays in the species' life-history. We exposed 7410 field-collected adult L. zonatus to temperatures between −2 and −10 °C for a period of three, four, or six hours using insect incubators. At six hours of exposure, the, LD50 and LD95 occur at −5.8 and −9.7 °C, respectively. We classified L. zonatus as chill-intolerant. Temperatures cold enough to affect substantial mortality of overwintering L. zonatus rarely occur in the San Joaquin Valley. Whole aggregation destructive sampling from a pomegranate hedgerow in Fresno County was conducted to determine population dynamics. At late summer to early fall, aggregations consisted of >90% immature stages. By early to mid-winter, mean aggregation size decreased, consisting of only three to 12 late-instars and adults. During years one and two of the experiment, L. zonatus produced a generation on pomegranate, mostly between September and mid-November. Overwintering did not occur on pomegranate, rather the majority of adults emigrated to other overwintering locations by mid-winter. [ABSTRACT FROM AUTHOR]