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Strandings have been extensively documented for large mammals, however, a comprehensive survey focusing on batoids is currently lacking. To address this knowledge gap, we conducted a review of available stranding data sourced from iNaturalist, news websites, and published papers. A total of 3.148 reports encompassing 189 batoid species were recovered, revealing the vulnerability of both oceanic and coastal species to strandings. Nevertheless, limited data on life stage, sex, animal condition, and fate hinder a comprehensive understanding of this phenomenon. Putative causes were identified only for a small percentage (6%) of the reports, namely pollution, abrupt environmental alterations, predation, pathologies, and fishing activities. The earliest reported stranding dates back to 1989, with an increase in reports observed since 2019. iNaturalist accounted for the majority (75%) of records, emphasizing its significance as a platform for reporting and monitoring batoid strandings. These strandings were reported in 51 countries, with the coastal areas of California, United States, particularly notable. Among the identified species, Rhinoptera bonasus exhibited the highest number of strandings, with 392 recorded individuals. Alarmingly, more than half of the reports involved threatened species, underscoring the need for increased attention to batoid strandings. To address these issues, we propose the establishment of stranding monitoring networks and the development of a freely accessible global database. In addition, the training of volunteer citizen scientists, the development of rescue and rehabilitation protocols, and manuals of good fishing practices aimed at commercial and recreational fisheries are also recommended. [ABSTRACT FROM AUTHOR]

Morro manzanita Arctostaphyos morroensis (Ericaceae) is a long-lived, shrub endemic to San Luis Obispo County, southern California, USA. It was listed as threatened under the U.S. Endangered Species Act in 1994, with identified threats being residential and urban development, including lack of protection on private land and lack of management on public lands, competition with invasive non-native plants, and risks of extinction associated with small and isolated populations. Our goal in this paper is to summarize and supplement the current knowledge of Morro manzanita. We review the literature on the species' description, reproductive ecology, germination cues, short-term response to fire. and distribution. We conducted field surveys to report on long-term response to fire, resampling the previously studied prescribed burn site 25 yr post-fire. Finally, we summarize the current land management of sites that support Morro manzanita and threats faced by this species. We conclude with specific recommendations for management and future study towards supporting conservation of this species and its maritime chaparral community. [ABSTRACT FROM AUTHOR]

This paper uses videotaping and discourse analysis to study participants' dialogue and conduct during preparation of the Coachella Valley habitat conservation plan in southern California. The research uses social worlds analysis to reveal that the plan's technical advisors did not find facts through the collective discovery of scientific truths with unitary meanings, but instead constructed facts by aligning professional visions of space, time, and agency. The validity of the resulting plan relied on its ability to be a 'boundary object', meaning different things to different groups, while simultaneously laying claim to universality and objectivity. However, its subsequent failure to satisfy an unexpected scientific peer review demonstrates the importance of anticipating downstream reception and use when developing such documents. This case study shows that planners can be epistemic mediators, creating and stabilizing technical knowledge claims that project authority by showing a responsive face to many audiences. [ABSTRACT FROM AUTHOR]

The Sweetwater Authority's urban runoff diversion system (URDS) comprises constructed wetlands on a hillside between the town of Spring Valley and the Sweetwater Reservoir, California, USA. The URDS were designed to divert dry-weather and first-flush urban runoff flows from the Sweetwater reservoir. However, these constructed wetlands have developed into ecologically valuable habitat. This paper evaluates the following ecological questions related to the URDS: (1) the natural development of the species present and their growth pattern; (2) the biodiversity and pollutant stress on the plants and invertebrates; and (3) the question of habitat provided for endangered species. The URDS wetlands are comprised primarily of rush (Scirpus spp.) and cattails (Typha spp.). This vegetative cover ranged from 39-78% of the area of the individual wetland ponds. Current analyses of plant tissues and wetland sediment indicates the importance of sediment sorption for metals and plant uptake of nutrients. Analyses of URDS water following runoff events show the URDS wetlands do reduce the amount of nutrients and metals in the water column. Invertebrate surveys of the wetland ponds revealed lower habitat quality and environmental stress compared to unpolluted natural habitat. The value of the wetlands as wildlife habitat is constrained by low plant biodiversity and pollution stress from the runoff. Since the primary Sweetwater Authority goal is to maintain good water quality for drinking, any secondary utilization of URDS habitat by species (endangered or otherwise) is deemed an added benefit. [ABSTRACT FROM AUTHOR]

In recent years, population viability analysis has become a popular tool to assess the relative risk of extinction among populations. Viability estimates for spatially structured populations require movement data that are often unavailable. In this paper, a diffusion approximation model was used to explore the effects of different spatial scenarios resulting from assumptions about movement rates. Census data for 13 breeding islands occupied by California sea lions Zalophus californianus californianus in the Gulf of California were used to explore three potential scenarios: unlimited movement between sites (panmictic population), limited movement (several clusters of populations) and no movement between islands (isolated islands). Predicted viability estimates were different for each scenario, but contrary to expectations, the mean extinction risk estimates were generally lowest when movement was unlimited (panmictic scenario). However, despite an extensive dataset, the confidence of the viability predictions for each scenario was low. In some cases, uncertainty in predictions within a scenario was greater than differences between scenarios. Therefore, it is recommended that in situations where movement rates and spatial structure are unknown, extinction risk estimates should reflect both the confidence intervals for each risk estimate and the uncertainty resulting from different spatial scenarios. This study also provides the first estimate of population viability (considering spatial structure) for California sea lions in the Gulf of California and an evaluation of population status based on the IUCN criteria for species listing. [ABSTRACT FROM AUTHOR]

Under the Endangered Species Act, the U.S. Fish and Wildlife Service is required to designate critical habitat (CH) for listed species. Designation could result in modification to or delay of residential development projects within habitat boundaries, generating concern over potential housing market impacts. This paper draws upon a large data set of municipal-level (FIPS) building permit issuances and critical habitat designations (CHDs) in California over a 13-year period to identify changes in the spatial and temporal pattern of development activity associated with CHD. We find that the proposal of the median-sized CH results in a 23.5 percent decrease in the supply of housing permits in the short run and a 37.0 percent decrease in the long run. The results indicate the proposal of CH acts as a signal that all development in that FIPS will be more costly. We also find that the impact varies across the two periods in which CH is designated and by the number of years relative to when CH was first proposed. [ABSTRACT FROM AUTHOR]

The article presents information on research papers related to endangered species. The paper "Experimental Comparison of Reintroduction Methods for the Endangered Echinacea laevigata (Boynton and Beadle) Blake," by H. Alley and J.M. Affolter tests propagation techniques for smooth coneflower, a federally endangered species of the southeastern United States Piedmont. The paper "Close Encounters of an Avian Kind," by A. Canright describes the process of raising, releasing and monitoring six California condors at Pinnacles National Monument. The paper "Colonization History and Noninvasive Monitoring of a Reestablished Wolverine Population," by Ø Flagstad, E. Hedmark, A. Landa, H. Brøseth, J. Persson, R. Andersen, P. Segerstrom and H. Ellegren reports on a large-scale monitoring project assessing population characteristics of southern Norwegian wolverines through genetic tagging of individuals, with feces as a DNA source. The results suggest that male wolverines can disperse up to 311 miles and that the southern population is being augmented by northern wolverine immigrants.