Wildlife response to human activity in San Diego County, California

Most natural areas are set aside for multiple reasons, such as conserving plants and animals, providing places for outdoor recreation, and protecting unique natural features. But we don't always know if all these purposes can be accomplished simultaneously. Recently, participation in non-consumptive outdoor recreation (such as hiking, mountain biking, and trail running) has been increasing nationally and globally. While this is great news for public health and appreciation of nature, it also raises concerns ranging from emissions from traffic in national parks to soil erosion to the introduction of invasive species.
San Diego County has a population of over three million people. It is also a hotspot of biodiversity that is home to over 500 vertebrate species, many of which are threatened or endangered. In a collaboration among the Wildlife Conservation Society, Colorado State University, and University of California-Berkeley, we are working to measure and model recreation in San Diego parks and preserves to assess the risk of disturbance to sensitive wildlife species. The fieldwork for this project began in the summer of 2013, when we measured recreation patterns in 18 parks and preserves throughout the San Diego area. We identified several important factors that we believe contribute to recreational use, including the number of parking lots, the number of nearby housing units, and the proximity to other parks and preserves.
Continuing work on this project involves monitoring reptile and mammal communities at points along recreational trails that receive varying levels of human use. Our goal is to assess whether there are trends in reptile and mammal abundance, occurrence, or community composition that can be related to the level of recreational use, while controlling for other important factors such as weather, vegetation community, and time of year. Rather than attempting to shut down access for recreationists, we are simply trying to understand the potential trade-offs between outdoor recreation and wildlife conservation. We hope that with a better understanding of the impacts of outdoor recreation, we can help design management strategies to make protected areas work effectively for people and a diverse assemblage of native wildlife species.
San Diego County has a population of over three million people. It is also a hotspot of biodiversity that is home to over 500 vertebrate species, many of which are threatened or endangered. In a collaboration among the Wildlife Conservation Society, Colorado State University, and University of California-Berkeley, we are working to measure and model recreation in San Diego parks and preserves to assess the risk of disturbance to sensitive wildlife species. The fieldwork for this project began in the summer of 2013, when we measured recreation patterns in 18 parks and preserves throughout the San Diego area. We identified several important factors that we believe contribute to recreational use, including the number of parking lots, the number of nearby housing units, and the proximity to other parks and preserves.
Continuing work on this project involves monitoring reptile and mammal communities at points along recreational trails that receive varying levels of human use. Our goal is to assess whether there are trends in reptile and mammal abundance, occurrence, or community composition that can be related to the level of recreational use, while controlling for other important factors such as weather, vegetation community, and time of year. Rather than attempting to shut down access for recreationists, we are simply trying to understand the potential trade-offs between outdoor recreation and wildlife conservation. We hope that with a better understanding of the impacts of outdoor recreation, we can help design management strategies to make protected areas work effectively for people and a diverse assemblage of native wildlife species.
Systematic literature review of the effects of recreation on wildlife
Recreation is a very common use of protected areas worldwide; a recent study estimated that protected areas receive 8 billion visits per year, and some form of recreation is permitted in over 94% of the protected areas that have been classified by the International Union for Conservation of Nature (IUCN). These types of human use are typically assumed to be compatible with biodiversity conservation. While recreation has numerous benefits for human health, livelihoods, and conservation funding and support, there are also concerns about its effects on wildlife that these protected areas are charged with conserving.
There are a growing number of studies that examine effects of recreation on wildlife. A few existing papers review sub-sections of this body of literature; for example, Sato et al. (2013) review effects of winter recreation on alpine wildlife, and Martinez-Abrain et al. (2010) review the literature on how recreation affects birds of prey. Our goal was to take a broader view and conduct a review that included all types of recreation, all animal species, anywhere in the world. We used a systematic review process to identify 218 peer-reviewed journal articles that measured effects of recreation on wildlife. We are examining the distribution of these studies by taxonomic group, study location, response type (e.g., abundance, species richness, reproductive success), and recreation activity to see if there are key gaps in our knowledge on this topic. We're also exploring the effects that these articles found.
This is an area deserving much more research. Finding an appropriate balance between biodiversity conservation and outdoor recreation is complicated, especially since impacts vary among species and recreation activities, and because recreation is an integral part of protected areas worldwide. But it is a goal that we must work toward in order to minimize our impacts on the species that we want to conserve in our protected areas.
There are a growing number of studies that examine effects of recreation on wildlife. A few existing papers review sub-sections of this body of literature; for example, Sato et al. (2013) review effects of winter recreation on alpine wildlife, and Martinez-Abrain et al. (2010) review the literature on how recreation affects birds of prey. Our goal was to take a broader view and conduct a review that included all types of recreation, all animal species, anywhere in the world. We used a systematic review process to identify 218 peer-reviewed journal articles that measured effects of recreation on wildlife. We are examining the distribution of these studies by taxonomic group, study location, response type (e.g., abundance, species richness, reproductive success), and recreation activity to see if there are key gaps in our knowledge on this topic. We're also exploring the effects that these articles found.
This is an area deserving much more research. Finding an appropriate balance between biodiversity conservation and outdoor recreation is complicated, especially since impacts vary among species and recreation activities, and because recreation is an integral part of protected areas worldwide. But it is a goal that we must work toward in order to minimize our impacts on the species that we want to conserve in our protected areas.