Past exploitation of california sea lions did not lead to a genetic bottleneck in the Gulf of California | La explotación histórica del lobo marino de california no causó un cuello de botella genético en el Golfo de California

Human exploitation can lead to genetic bottlenecks associated with reduced genetic variability and lower fitness. The population of California sea lions (Zalophus californianus) in the Gulf of California, Mexico, was hunted during the 19th and 20th centuries, potentially leading to a genetic bottleneck; however, even exploitation that leads to low population sizes does not always cause genetic bottlenecks. Understanding the genetic consequences of past sea lion hunts is critical to the conservation of the Gulf of California sea lion population, which is currently declining and is genetically distinct from other populations. We used available data from 10 amplified polymorphic microsatellite loci in 355 individuals from six Mexican colonies. Microsatellite data were analyzed using diverse approaches (BOTTLENECK and M-ratio) to determine if a genetic bottleneck had occurred. Our results indicate that human exploitation did not cause a genetic bottleneck in the sea lion population of the Gulf of California. Simulation analyses revealed that a reduction in genetic variability would have been detected if fewer than 100 individuals had remained after exploitation. We conclude that past exploitation was not as severe as previously thought and did not cause a genetic bottleneck in the Gulf of California sea lion population. Nevertheless, historical hunts specifically targeted adult males and this sexbiased exploitation may have influenced the population dynamics and overall fitness.Peer Reviewe

Human Disturbance Influences Reproductive Success and Growth Rate in California Sea Lions (Zalophus californianus)

The environment is currently undergoing changes at both global (e.g., climate change) and local (e.g., tourism, pollution, habitat modification) scales that have the capacity to affect the viability of animal and plant populations. Many of these changes, such as human disturbance, have an anthropogenic origin and therefore may be mitigated by management action. To do so requires an understanding of the impact of human activities and changing environmental conditions on population dynamics. We investigated the influence of human activity on important life history parameters (reproductive rate, and body condition, and growth rate of neonate pups) for California sea lions (Zalophus californianus) in the Gulf of California, Mexico. Increased human presence was associated with lower reproductive rates, which translated into reduced long-term population growth rates and suggested that human activities are a disturbance that could lead to population declines. We also observed higher body growth rates in pups with increased exposure to humans. Increased growth rates in pups may reflect a density dependent response to declining reproductive rates (e.g., decreased competition for resources). Our results highlight the potentially complex changes in life history parameters that may result from human disturbance, and their implication for population dynamics. We recommend careful monitoring of human activities in the Gulf of California and emphasize the importance of management strategies that explicitly consider the potential impact of human activities such as ecotourism on vertebrate populations

The Role of Landscape Connectivity in Planning and Implementing Conservation and Restoration Priorities. Issues in Ecology

Landscape connectivity, the extent to which a landscape facilitates the movements of organisms and their genes, faces critical threats from both fragmentation and habitat loss. Many conservation efforts focus on protecting and enhancing connectivity to offset the impacts of habitat loss and fragmentation on biodiversity conservation, and to increase the resilience of reserve networks to potential threats associated with climate change. Loss of connectivity can reduce the size and quality of available habitat, impede and disrupt movement (including dispersal) to new habitats, and affect seasonal migration patterns. These changes can lead, in turn, to detrimental effects for populations and species, including decreased carrying capacity, population declines, loss of genetic variation, and ultimately species extinction. Measuring and mapping connectivity is facilitated by a growing number of quantitative approaches that can integrate large amounts of information about organisms’ life histories, habitat quality, and other features essential to evaluating connectivity for a given population or species. However, identifying effective approaches for maintaining and restoring connectivity poses several challenges, and our understanding of how connectivity should be designed to mitigate the impacts of climate change is, as yet, in its infancy. Scientists and managers must confront and overcome several challenges inherent in evaluating and planning for connectivity, including: •characterizing the biology of focal species; •understanding the strengths and the limitations of the models used to evaluate connectivity; •considering spatial and temporal extent in connectivity planning; •using caution in extrapolating results outside of observed conditions; •considering non-linear relationships that can complicate assumed or expected ecological responses; •accounting and planning for anthropogenic change in the landscape; •using well-defined goals and objectives to drive the selection of methods used for evaluating and planning for connectivity; •and communicating to the general public in clear and meaningful language the importance of connectivity to improve awareness and strengthen policies for ensuring conservation. Several aspects of connectivity science deserve additional attention in order to improve the effectiveness of design and implementation. Research on species persistence, behavioral ecology, and community structure is needed to reduce the uncertainty associated with connectivity models. Evaluating and testing connectivity responses to climate change will be critical to achieving conservation goals in the face of the rapid changes that will confront many communities and ecosystems. All of these potential areas of advancement will fall short of conservation goals if we do not effectively incorporate human activities into connectivity planning. While this Issue identifies substantial uncertainties in mapping connectivity and evaluating resilience to climate change, it is also clear that integrating human and natural landscape conservation planning to enhance habitat connectivity is essential for biodiversity conservation

Five approaches to producing actionable science in conservation

peer reviewedThe knowledge produced by conservation scientists must be actionable in order to address urgent conservation challenges. To understand the process of creating actionable science, we interviewed 71 conservation scientists who had participated in 1 of 3 fellowship programs focused on training scientists to become agents of change. Using a grounded theory approach, we identified 16 activities that these researchers employed to make their scientific products more actionable. Some activities were more common than others and, arguably, more foundational. We organized these activities into 3 nested categories (motivations, strategies, and tactics). Using a co-occurrence matrix, we found that most activities were positively correlated. These correlations allowed us to identify 5 approaches, framed as profiles, to actionable science: the discloser, focused on open access; the educator, focused on science communication; the networker, focused on user needs and building relationships; the collaborator, focused on boundary spanning; and the pluralist, focused on knowledge coproduction resulting in valuable outcomes for all parties. These profiles build on one another in a hierarchy determined by their complexity and level of engagement, their potential to support actionable science, and their proximity to ideal coproduction with knowledge users. Our results provide clear guidance for conservation scientists to generate actionable science to address the global biodiversity conservation challenge.Cinco estrategias para producir ciencia práctica en la conservación Resumen El conocimiento producido por los científicos de la conservación debe ser práctico para poder abordar los obstáculos urgentes que enfrenta la conservación. Entrevistamos a 71 científicos de la conservación que participaron en uno de los tres programas de becas enfocados en la formación de científicos como agentes de cambio para entender el proceso de creación de la ciencia práctica. Usamos una estrategia de teoría fundamentada para identificar 16 actividades empleadas por estos investigadores para hacer más prácticos sus productos científicos. Algunas actividades fueron más comunes que otras y, probablemente, más fundamentales. Organizamos estas actividades en tres categorías anidadas: motivaciones, estrategias y tácticas. Con una matriz de co-ocurrencia, encontramos que la mayoría de las actividades estaban correlacionadas positivamente. Estas correlaciones nos permitieron identificar cinco estrategias, encuadradas como perfiles, para la ciencia práctica: la reveladora, enfocada en el acceso abierto; la educativa, enfocada en la comunicación de la ciencia; la interconectora, enfocada en las necesidades del usuario y en construir relaciones; la colaborativa, enfocada en la expansión de las fronteras; y la pluralista, enfocada en la coproducción del conocimiento como el origen de resultados valiosos para todas las partes. Estas estrategias se apoyan entre sí en una jerarquía determinada por su complejidad y el nivel de compromiso, su potencial para apoyar la ciencia práctica y su proximidad a la coproducción ideal con los usuarios del conocimiento. Nuestros resultados proporcionan directrices claras para que los científicos de la conservación generen ciencia práctica para abordar los retos de conservación que enfrenta la biodiversidad mundial.保护科学家必须产出可操作的知识, 才能应对紧迫的保护挑战。为了解创造可操作科学的过程, 我们采访了71位保护科学家, 他们参与了培养科学家成为变革者的三项奖金项目中的一项。基于扎根理论方法, 我们确定了这些研究者为创造可操作的科学产出而开展的16项活动。有些活动比其他活动更为常见, 并且可以说是更为基础。我们将这些活动分为三个嵌套的类别(动机、策略和战术)。利用共生矩阵, 我们发现大多数活动是正相关的, 且基于这些相关性可以确定出五种方法, 作为可操作科学的框架:专注于开放存取的公开者;专注于科学交流的教育者;专注于使用者需求和建立关系的网络者;专注于跨越边界的合作者;以及专注于知识协同生产、为各方带来有价值结果的多元主义者。这些特征相互建立在一个层级结构上, 而这个层级结构由其复杂性和参与度、支持可操作科学的潜力, 以及与知识使用者理想的协同生产的接近度决定。本研究的结果为保护科学家产出可操作科学以应对全球生物多样性保护挑战提供了明确的指导。 【胡怡思; 审校: 聂永刚】

First Evidence for Adoption in California Sea Lions

Demographic parameters such as birth and death rates determine the persistence of populations. Understanding the mechanisms that influence these rates is essential to developing effective management strategies. Alloparental behavior, or the care of non-filial young, has been documented in many species and has been shown to influence offspring survival. However, the role of alloparental behavior in maintaining population viability has not been previously studied. Here, we provide the first evidence for adoption in California sea lions and show that adoption potentially works to maintain a high survival rate of young and may ultimately contribute to population persistence. Alloparental behavior should have a positive effect on the population growth rate when the sum of the effects on fitness for the alloparent and beneficiary is positive

Bringing sustainability to life: A framework to guide biodiversity indicator development for business performance management

Biodiversity loss is a critical sustainability issue, and companies are beginning to seek ways to assess their biodiversity performance. Initiatives to date have developed biodiversity indicators for specific business contexts (e.g., spatial scales – from site, to product, to regional, or corporate scales), however many are not widely translatable across different contexts making it challenging for businesses seeking indicators to manage their biodiversity performance. By synthesizing the steps of common conservation and business decision-making systems, we propose a framework to support more comprehensive development of quantitative biodiversity indicators, for a range of business contexts. The framework integrates experience from existing tried-and-tested conservation frameworks. We illustrate how our framework offers a pathway for businesses to assess their biodiversity performance, and demonstrate responsible management by mitigating and reversing their biodiversity impacts and sustaining their dependencies, enabling them to demonstrate their contribution to emerging global biodiversity targets (e.g., Convention on Biological Diversity post-2020 targets)

Foundations of Translational Ecology

Ecologists who specialize in translational ecology (TE) seek to link ecological knowledge to decision making by integrating ecological science with the full complement of social dimensions that underlie today\u27s complex environmental issues. TE is motivated by a search for outcomes that directly serve the needs of natural resource managers and decision makers. This objective distinguishes it from both basic and applied ecological research and, as a practice, it deliberately extends research beyond theory or opportunistic applications. TE is uniquely positioned to address complex issues through interdisciplinary team approaches and integrated scientist–practitioner partnerships. The creativity and context-specific knowledge of resource managers, practitioners, and decision makers inform and enrich the scientific process and help shape use-driven, actionable science. Moreover, addressing research questions that arise from on-the-ground management issues – as opposed to the top-down or expert-oriented perspectives of traditional science – can foster the high levels of trust and commitment that are critical for long-term, sustained engagement between partners

A scientific synthesis of marine protected areas in the United States: status and recommendations

Marine protected areas (MPAs) are a key tool for achieving goals for biodiversity conservation and human well-being, including improving climate resilience and equitable access to nature. At a national level, they are central components in the U.S. commitment to conserve at least 30% of U.S. waters by 2030. By definition, the primary goal of an MPA is the long-term conservation of nature; however, not all MPAs provide the same ecological and social benefits. A U.S. system of MPAs that is equitable, well-managed, representative and connected, and includes areas at a level of protection that can deliver desired outcomes is best positioned to support national goals. We used a new MPA framework, The MPA Guide, to assess the level of protection and stage of establishment of the 50 largest U.S. MPAs, which make up 99.7% of the total U.S. MPA area (3.19 million km2). Over 96% of this area, including 99% of that which is fully or highly protected against extractive or destructive human activities, is in the central Pacific ocean. Total MPA area in other regions is sparse – only 1.9% of the U.S. ocean excluding the central Pacific is protected in any kind of MPA (120,976 km2). Over three quarters of the non-central Pacific MPA area is lightly or minimally protected against extractive or destructive human activities. These results highlight an urgent need to improve the quality, quantity, and representativeness of MPA protection in U.S. waters to bring benefits to human and marine communities. We identify and review the state of the science, including focal areas for achieving desired MPA outcomes and lessons learned from places where sound ecological and social design principles come together in MPAs that are set up to achieve national goals for equity, climate resilience, and biodiversity conservation. We recommend key opportunities for action specific to the U.S. context, including increasing funding, research, equity, and protection level for new and existing U.S. MPAs

Weak Polygyny in California Sea Lions and the Potential for Alternative Mating Tactics

Female aggregation and male territoriality are considered to be hallmarks of polygynous mating systems. The development of genetic parentage assignment has called into question the accuracy of behavioral traits in predicting true mating systems. In this study we use 14 microsatellite markers to explore the mating system of one of the most behaviorally polygynous species, the California sea lion (Zalophus californianus). We sampled a total of 158 female-pup pairs and 99 territorial males across two breeding rookeries (San Jorge and Los Islotes) in the Gulf of California, Mexico. Fathers could be identified for 30% of pups sampled at San Jorge across three breeding seasons and 15% of sampled pups at Los Islotes across two breeding seasons. Analysis of paternal relatedness between the pups for which no fathers were identified (sampled over four breeding seasons at San Jorge and two at Los Islotes) revealed that few pups were likely to share a father. Thirty-one percent of the sampled males on San Jorge and 15% of the sampled males on Los Islotes were assigned at least one paternity. With one exception, no male was identified as the father of more than two pups. Furthermore, at Los Islotes rookery there were significantly fewer pups assigned paternity than expected given the pool of sampled males (p<0.0001). Overall, we found considerably lower variation in male reproductive success than expected in a species that exhibits behavior associated with strongly polygynous mating. Low variation in male reproductive success may result from heightened mobility among receptive females in the Gulf of California, which reduces the ability of males to monopolize groups of females. Our results raise important questions regarding the adaptive role of territoriality and the potential for alternative mating tactics in this species

Quantifying the Spatial Ecology of Wide-Ranging Marine Species in the Gulf of California: Implications for Marine Conservation Planning

There is growing interest in systematic establishment of marine protected area (MPA) networks and representative conservation sites. This movement toward networks of no-take zones requires that reserves are deliberately and adequately spaced for connectivity. Here, we test the network functionality of an ecoregional assessment configuration of marine conservation areas by evaluating the habitat protection and connectivity offered to wide-ranging fauna in the Gulf of California (GOC, Mexico). We first use expert opinion to identify representative species of wide-ranging fauna of the GOC. These include leopard grouper, hammerhead sharks, California brown pelicans and green sea turtles. Analyzing habitat models with both structural and functional connectivity indexes, our results indicate that the configuration includes large proportions of biologically important habitat for the four species considered (25–40%), particularly, the best quality habitats (46–57%). Our results also show that connectivity levels offered by the conservation area design for these four species may be similar to connectivity levels offered by the entire Gulf of California, thus indicating that connectivity offered by the areas may resemble natural connectivity. The selected focal species comprise different life histories among marine or marine-related vertebrates and are associated with those habitats holding the most biodiversity values (i.e. coastal habitats); our results thus suggest that the proposed configuration may function as a network for connectivity and may adequately represent the marine megafauna in the GOC, including the potential connectivity among habitat patches. This work highlights the range of approaches that can be used to quantify habitat protection and connectivity for wide-ranging marine species in marine reserve networks