Between 1 February 2012 and 26 February 2014 using scuba, we surveyed the fishes, invertebrates, and macrophytes living on two energized submarine power cables, an adjacent pipe, and nearby natural habitat in southern California at bottom depths of 10–11 m and 13–14 m. Over the course of the study, average electromagnetic field (EMF) levels at the two cables (A and B) were statistically similar (Cable A = 73.0µT, Cable B = 91.4µT) and were much higher at these two cables than at either the pipe (average = 0.5µT) or sand (0µT). Overall, our study demonstrated that 1) the fish and invertebrate communities on cables, pipe, and natural habitat strongly overlapped and 2) there were no differences between the shallower and deeper fish and invertebrate communities. We saw no evidence that fishes or invertebrates are either preferentially attracted to, or repelled by, the EMF emitted by the cables. Any differences in the fish or invertebrate densities between cables, pipe, and natural habitat taxa were most likely due to the differences in the physical characteristics of these habitats. As with the fishes and invertebrates, macrophytes did not appear to be responding to the EMF emitted by the cables. Rather, it is likely that differences in the plant communities were driven by site depth and habitat type.

Restored estuaries in southern California are limited in size and shape by fragmentation from human development, which can in turn restrict habitat use. Thus, it is important to assess how habitat design affects how fish use restored estuaries. Acoustic telemetry tracking from prior studies revealed that Gray Smoothhounds (Mustelus californicus) used primarily the eelgrass ecotone and warm interior waters in Bolsa Chica Full Tidal Basin (BCFTB), a 1.48 km² open-format marine dominated estuary. In this study, M. californicus utilized the Channel in Huntington Beach Wetlands Complex (HBWC), a smaller creek estuary. The Channel had more eelgrass than other available habitats but was also the coolest microhabitat, with temperatures below what M. californicus was found to select in BCFTB. Individuals may behaviorally thermoregulate by moving upstream, away from the HBWC Channel, during periods of incoming, cooler ocean water. Mustelus californicus translocated to different microhabitats within the HBWC selected the Channel habitat after the translocation regardless of where animals were released. Despite the large difference in available subtidal habitat between HBWC and BCFTB, no differences in patch size utilization distributions of M. californicus were observed. While individuals seem to shift between microhabitats based on temperature and eelgrass availability, the area size used by M. californicus appears to be the same within both sites despite the differences in overall size between sites. These results suggest that differences in microhabitat use may influence distribution patterns of M. californicus within each site, and therefore, shark abundance may vary with the restoration design (e.g. basin versus channel) and the size of the estuarine habitat. This information on habitat selection will be critical to planning future restorations on the Southern California coast.

Young-of-the-year Giant Sea Bass (Stereolepis gigas) (hereafter YOY GSB) spend the first several months after planktonic settlement within recreational dive limits. After settlement, YOY GSB morph through pigmentation phases where patterns of black spots unique to individual fish appear against the fish's lighter background. In order to prove that underwater photographs of spot patterns could be used to individually identify and possibly track YOY GSB in the field, several YOY GSB were captured and raised at public aquaria. Both sides of each fish were planned to be photographed monthly for a year from the capture date. The black spots of YOY GSB are so few and distinct that computer programs developed to discern individuals of species with complicated spot patterns were not necessary for re-identification of individuals. Three fish that were followed for twelve months in captivity could be individually identified by comparing photographs of their spot patterns by eye. A fourth fish that survived for six months could also be individually distinguished through photographs. This is the first published study to follow the development of YOY GSB spot patterns. Underwater photo-identification techniques could be used to re-identify individuals from several months to at least a year after planktonic settlement. That no capture-recapture studies have been conducted on YOY GSB to date hinders the basic understanding of species ecology and population dynamics. This study opens the door to the use of underwater photography as a passive mark and recapture method for studying YOY GSB along soft-bottomed nursery beaches where they can be found for the first few months after settlement.

Land snails in the family Helminthoglyptidae are found sparingly and locally throughout southern California's deserts. They are mostly restricted to rock outcrops and talus in partially shaded canyons where they can gain access to cooler temperatures under the rocks. Several species are known only from their type localities, and were described by shell characters only. We have endeavored to locate known species, document their reproductive anatomy and embryonic shell structure, refine knowledge of their distribution, and incorporate genetic sequencing of two mitochondrial genes (COI and 16S) to investigate evolutionary relationships in these taxa. As a “first pass” molecular study, we have established basic sequence and divergence data for 27 populations of snails in five genera: Helminthoglypta (subgenus Coyote), Eremarionta, Cahuillus, Chamaearionta and Sonorelix. Fifteen of the populations were previously unknown. We confirmed that the Salton Rift/Coachella Valley is a major biogeographic barrier for land snails, as is the north/south transition between the Colorado and Mojave deserts. Described species of Helminthoglypta (Coyote) grouped together in our phylogenetic analyses and differed from each other by 8-18% in the sequence of the COI gene, concordant with differentiating shell characters. Two previously unknown populations grouped with the Coyote species but their COI sequences differed from the described species by 5.7-17% suggesting they may represent undescribed Coyote species. Populations of Sonorelix from the eastern Mojave were somewhat similar genetically to Sonorella spp. from southern Arizona but the precise nature of any relationship between these genera remains unresolved. The remaining, previously unknown populations were genetically close to described species of Eremarionta, but inclusion of COI sequences of two Cahuillus spp. rendered the genus Eremarionta paraphyletic, raising questions about the validity of the names applied to some described species. In particular, the subspecies E. rowelli bakerensis was clearly different (>11% in COI) from E. rowelli amboiana and E. rowelli acus, and deserves elevation to at least species status. The eastern Mojave Eremarionta from near Pahrump, Nevada may also be an undescribed species, differing in its COI sequence from its closest described relative by 6.0%. Perhaps the most surprising result from our study was the finding of a population close to the Salton Sea that was very closely related to E. rowelli ssp. bakerensis which occurs ∼200 km further north. This highlights the complex nature of genetic variation among geographically isolated Eremarionta populations across the eastern Mojave and western Colorado Deserts.