Mitigation Ponds Offer Drought Resiliency for Western Spadefoot (Spea hammondii) Populations

Synergistic effects of habitat loss, drought, and climate change exacerbate amphibian declines. In southern California urbanization continues to convert natural habitat, while prolonged drought reduces surface water availability. Protection of biodiversity may be provided through mitigation; however, the long-term effectiveness of different strategies is often unreported. As a mitigation measure for building a new development within occupied Spea hammondii (western spadefoot) habitat in Orange County, California, artificial breeding pools were constructed at two off-site locations. Spea hammondii tadpoles were translocated from the pools at the development site to two off-site locations in 2005–2006. We conducted surveys a decade later (2016) to determine if S. hammondii were persisting and breeding successfully at either the original development site or the human-made pools at the two mitigation sites. We also verified hydroperiods of any existing pools at all three locations to see if any held water long enough for successful S. hammondii recruitment through metamorphosis. During our study, no pooling water was detected at two of three main sites surveyed, and no S. hammondii were observed at these locations. Twelve of the 14 pools created at only one of the two mitigation sites held water for over 30 d, and we detected successful breeding at seven of these pools. Recruitment in some mitigation ponds indicated that S. hammondii habitat can be created and maintained over 10+ yr, even during the fifth year of a catastrophic drought. Therefore, this may also serve as a conservation strategy to mitigate climate change and habitat loss. During our study, no pooling water was detected at two of three main sites surveyed, and no S. hammondii were observed at these locations. Twelve of the 14 pools created at a third site held water for over 30 days and we detected successful breeding at seven of these pools in 2016. Recruitment in some mitigation ponds indicated that S. hammondii habitat can be created and maintained over 10+ years, even during the fifth year of a catastrophic drought, therefore this may also serve as a management strategy for conservation with regard to climate change and habitat loss

Survival and Recruitment of Rehabilitated Caspian Terns in Southern California

Thousands of birds are taken in by animal care centers each year for rehabilitation. Birds returned to health by some centers are banded for later identification, but very few are ever reencountered following their return to the wild. We report here, information on the post-release survival of Caspian Terns (Hydroprogne caspia) in southern California as well as on their recruitment into a local breeding population and colony site fidelity

Are Fishes Attracted to Piers? Movements and Association of Marine Fishes to a Public Fishing Pier within a Commercial Harbor

Ocean fishing piers are ubiquitous along the world’s coastline, yet little research has examined how these structures can attract and retain fishes. Fishers routinely use these manmade structures as a reliable way to catch fish for subsistence or recreation. California halibut (Paralichthys californicus) and white croaker (Genyonemus lineatus) are commonly caught from fishing piers in southern California; however, some individuals have been found to contain high concentrations of hazardous contaminants. Thus, human health hazard warnings are posted throughout the Los Angeles area to limit fish consumption. To document attraction, residency, and association to fishing piers, forty-two California halibut and 198 white croaker were tagged with acoustic transmitters in regions of the Los Angeles and Long Beach Harbors, including a local fishing pier, and the movements of these fish were tracked throughout a 1.5 year period. Average (± SD) fish residency near piers was 90.5 ± 104.8 days for California halibut and 31.9 ± 25.7 days for white croaker. Only 18% of white croaker and 6% California halibut were detected migrating to the pier from other locations of the LA-LB Harbors, and most spent \u3c 10 min within 300 m of the public fish pier. Only 14% of California halibut and 0.35% of white croaker geo-positions were within casting range (approximately 30 m) of the pier, thus California halibut show the greatest potential affinity for pier habitat. Due to their movement patterns and habitat associations California halibut are much more likely to be attracted to fishing piers than white croaker

Protecting the WUI in California: Greenbelts vs thinning for wildfire threats to homes

This study utilized native chaparral and sage scrub shrubs to evaluate the impact of light summer irrigation on live fuel moisture content (LFMC) and predicted fire behavior. As to be expected LFMC varied markedly throughout the year being over 100% in winter in all species and treatments but differed markedly by treatment in the summer and fall. For most species lightly irrigated plants had the highest LFMC in the summer and fall, followed by thinned treatments and controls. These differences in moisture content coupled with structural differences in the vegetation contributed to expected differences in flame length and rate of spread. Lightly irrigated native shrubs planted around homes can reduce fire hazard and at the same time increase faunal diversity and other desirable features of utilizing native vegetation

Optimizing a Municipal Wastewater-based Chlorella vulgaris Photobioreactor for Sequestering Atmospheric CO2

Abstract. - Microalgae photobioreactors are among the most effective systems for capturing gaseous CO2, the main contributor to global warming. Their capacity to generate massive amounts of biomass has been exploited serendipitously to sequester CO2 and explicitly to remove nutrients from municipal wastewater. Unfortunately, research in this area has not included merging this dual capacity to address global warming. Instead, most are focused on thermolytic conversion of biomass into energy which in end returns CO2 to the atmosphere. In this study, we investigated the potential of combining the two microalgal capacities (that of deriving nutrients from municipal wastewater and metabolic carbon from atmospheric and/or industrial CO2 gas supplies), into an integrated means of reducing nutrients in ocean-bound wastewater and CO2 in the atmosphere simultaneously. The test species used in this study is Chlorella vulgaris (C. vulgaris); turbidity of C. vulgaris is used as a measure of yield in biomass. Our results show (i) that an open photobioreactor, and not a closed one, is the most productive, especially when augmented with industrial CO2 (hence making a strong case for scrubbing CO2 gas from industrial sources), (ii) that a mechanically agitated Chlorella vulgaris culture is more productive than a static one, (iv) that without mechanical agitation, 32 ± 3 days of incubation are needed to reach the maximum yield of an open photobioreactor, (iii) that the optimal proportion of wastewater (%WW) required to support C. vulgaris growth is 80 ± 3%; at least 33% WW is required to observe growth above background, and (v) that without intervention, the upper pH limit of a WW-based C. vulgaris culture is 8.69 ± 0.09. Two mutually independent models are proposed to aide in scaling up an open WW-based C. vulgaris photobioreactor

Temporal and Volumetric Characteristics of Lagoons in the Santa Monica Bay and the Passage Implications for Southern California Steelhead Trout

Record drought from 2012 to 2016 followed by rainfall in the winter of 2017 provided an opportunity to examine how changing climate conditions may affect migration opportunities for the endangered southern steelhead trout (Oncorhynchus mykiss). This study examined how intermittently open estuary-ocean interfaces in the Santa Monica Bay that have historically supported steelhead evolved temporally and volumetrically. All seven lagoons in the study area breached by January 2017 after five years of drought and nearly exclusively closed conditions. Duration of breach was affected by the size of the lagoon, with smaller lagoons remaining breached longer than larger lagoons. Conversely, volume capacity persisted longer in larger lagoons. Lagoon condition was quantified by presence/absence of breach and passibility, coupled with daily rainfall. This study provides important lagoon planning, restoration and management information needed to support recovery of southern steelhead trout populations in the face of climate change

Embodying Refusal: Resistance, Pathologization, and Mental Health Exemption in the Israel Defense Forces

This paper examines the cultural elements of obtaining a mental health exemption from military service in the Israel Defense Forces (IDF). This paper also examines the social inequalities that Israeli militarism creates within Israeli society which can motivate Israelis to avoid or refuse to complete mandatory military service. Often, an Israeli’s ethno-class affiliation influences why they might avoid or refuse to serve and affects how they refuse or attempt to gain an exemption from the military. I argue the IDF individualizes refusal and exemption as an attempt to mitigate social, political, and ethical claims and critiques about the military and Israeli society. Then, using findings from my field research, this paper discusses the practice of gaining a mental health exemption as a way to refuse military service. An individual seeking mental health exemption is required to embody the military’s interpretation of the “proper” symptoms of a pathologized mental disorder. I argue the military’s attempts to depoliticize mental health exemption by individualizing and pathologizing mental disorders as well as mental health exemption. I consider how mental health exemption can be resistance to militarism and military service. This paper examines how a military pathologizes mental health issues, depoliticizes avoidance and critique of the military, and informs how individuals practice resistance to military service by using the military’s own bureaucratic practices

Finding a resting place: How environmental conditions influence the habitat selection of resting batoids

Many batoid species will form aggregations while resting on the seafloor; however, the environmental variables that drive resting habitat selection behavior, and how it varies among species are not well understood. Bat rays (Myliobatis californica), shovelnose guitarfish (Pseudobatos productus), and round stingrays (Urobatis halleri) have been observed forming heterospecific aggregations. We investigated the effects of substrata type and seafloor water temperature as two likely variables that would influence resting habitat selection for these species. Spatial distribution patterns of individuals were determined via diver-based surveys over two survey seasons (Fall 2013 and Summer 2014) and related to detailed georeferenced habitat maps. While these batoids were found resting on both soft sediment types available, fine-sand was selected by all three species, whereas bat rays were the only one of the three species to select for vegetated-sand. The varying thermal sensitivities of the batoids likely influenced their responses to daily and seasonal temperatures within the study area. During Fall 2013, the three species were most abundant across a narrow temperature range (18.00 – 18.25°C); during Summer 2014, there were higher densities of bat rays in areas where daily maximum seafloor temperature reached 20°C. Each species demonstrated habitat selection decisions that were indicative of balancing tradeoffs between environmental variables. As K-selected, meso-level predators, aggregating in predictable ways can ultimately make batoids more susceptible to fishing and anthropogenic pressures. Therefore, knowledge of how batoids select their resting habitat and how environmental conditions shape distributions may provide managers with opportunities to implement better protection for resting species