DOCSLIB.ORG

Communicating Clearly About Conservation Corridors George R

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Communicating Clearly About Conservation Corridors George R Landscape and Urban Planning 55 =2001) 195±208 Communicating clearly about conservation corridors George R. Hessa,*, Richard A. Fischerb,1 aForestry Department, North Carolina State University, Raleigh, NC 27695-8002, USA bUS Army Engineer Research and Development Center, 3909 Halls Ferry Road, Vicksburg, MS 39180-6199, USA Received 22 August 2000; received in revised form 20 February 2001; accepted 26 February 2001 Abstract Con¯icting de®nitions lead to confusion when people communicate about `corridors', particularly when they come from different disciplinary backgrounds. Usage of `corridor' in game management, island biogeography, and metapopulation literature focused on function, namely, the movement of ¯ora and fauna from one area to another. A structural usage of the term arose in the ®eld oflandscape ecology as it developed in North America with the matrix±patch±corridor paradigm of landscape structure. `Corridor' is now used to describe both the structural and functional aspects of linear landscape features, often implicitly, in a wide range of disciplinary literature. Lack of a clear and consistent terminology leads to confusion about the goals or implied functions of corridors. Consequently, the manner in which corridors should be designed, managed, and evaluated is also unclear. Proper design and management ofa corridor depends critically on a clear and explicit statement ofits intended functions.Ifcorridors are not designed to perform well-de®ned functions, the outcome may be disappointing, or even deleterious. The roles corridors play derive from six ecological functions: habitat, conduit, ®lter, barrier, source, and sink. These ecological functions have been recognized widely and adopted by a number ofdisciplines, including conservation biology, wildlifemanagement, landscape ecology, and landscape planning. We review brie¯y the history ofthe term `corridor' in the context ofconservation, catalog some ofits de®nitions and uses, review the functions of corridors, and differentiate between the structural and functional aspects of corridors. We reject the notion ofde®ning `corridor' succinctly, because ofthe complex and multiple functionsa corridor may serve. Instead, we suggest that conservationists and planners consider and document explicitly all ofthe possible functionsofcorridors when designing them. Addressing explicitly these functions when designing a corridor should eliminate much of the confusion surrounding their roles, and focus attention on establishing design criteria for corridors that function as intended. # 2001 Elsevier Science B.V. All rights reserved. Keywords: Conservation corridors; Habitat fragmentation; Metapopulation literature ``Landscape linkages, land bridges, wildlife cor- ridors, greenways, shelterbelts, turkey trots Ð call them what you will.'' Chadwick =1991: xxi): ``Perhaps the generation ofoverarching princi- ples for the evaluation and design of corridors * Corresponding author. Tel.: 1-919-515-7437; could be assisted by the development ofmore fax: 1-919-515-8149. rigorous definitions that reflect the range of E-mail addresses: [email protected] =G.R. Hess), [email protected] =R.A. Fischer). potential values ofretained areas fornature con- 1 Tel.: 1-601-634-3983. servation.'' Lindenmayer and Nix =1993: 629) 0169-2046/01/$20.00 # 2001 Elsevier Science B.V. All rights reserved. PII: S 0169-2046=01)00155-4 196 G.R. Hess, R.A. Fischer / Landscape and Urban Planning 55 52001) 195±208 1. Introduction from many disciplines. Instead, we propose that con- servationists and planners consider and document Habitat loss and fragmentation have been cited explicitly all ofthe possible functions ofcorridors widely as the major contemporary threats to biologi- when designing them. cal diversity as people transform the landscape to accommodate their needs =e.g. Harris, 1984; Wilson, 1988; Saunders et al., 1991; Alverson et al., 1994; 2. Brief history and de®nitions McCullough, 1996; Pickett et al., 1997; Fielder and Kareiva, 1998). Corridors have become popular tools Corridors for faunal movement have a relatively in efforts to mitigate fragmentation and conserve long history in game management =Harris, 1984, biodiversity, but the term is used in ways that can 1988; Harris and Scheck, 1991). They have been used be contradictory and confusing. as a conservation technique since early in the 20th Numerous researchers working with corridors have century, particularly for birds =see extensive list of noted that lack ofa clear and consistent terminology examples in Harris and Scheck, 1991). Indeed, a sys- leads to confusion about the goals of corridors =Saun- tem of stepping-stone wildlife refuges is central to the ders and Hobbs, 1991a; Loney and Hobbs, 1991; migratory corridor planning critical to the restoration Simberloff et al., 1992; Lindenmayer and Nix, 1993; ofwaterfowl populations in North America. Other Rosenberg et al., 1995, 1997; Hobbs and Wilson, game species, including tree squirrels and ungulates, 1998; Bennett, 1999). Consequently, the manner in also have been the subject ofcorridor management which corridors should be designed, managed, and =Harris, 1988; Harris and Scheck, 1991). evaluated is also unclear. Ifcorridors are not designed More recently, corridors have been associated with to perform a well-de®ned function, the outcome may the theories ofisland biogeography =MacArthur and be disappointing, or even deleterious. The situation is Wilson, 1967) and metapopulations =e.g. Levins, further confounded when one considers de®nitions 1969; McCullough, 1996; Hanksi and Gilpin, 1997). across the several disciplines that use the term: con- These two theories form the basis for many current servation biology, landscape ecology, landscape and approaches to conservation biology, including the use urban planning, and landscape architecture. ofcorridors to enhance the movement of¯ora and Some conservation biologists have attempted to fauna. In island biogeography, the number of species de®ne the term `corridor' succinctly and precisely, on an island is a function of island size and the rates at often by focusing on a speci®c function =e.g. Loney which species immigrate to and become extinct on the and Hobbs, 1991; Beier and Loe, 1992; Simberloff island =MacArthur and Wilson, 1967). This concept et al., 1992; Rosenberg et al., 1995, 1997). However, has been extended by analogy to `islands' ofhabitat because corridors serve a variety offunctions at many embedded in a hostile landscape. By enhancing the scales, the concepts and terms associated with them ability ofspecies to move among these islands, corri- defy simple de®nition. Many de®nitions have excep- dors increase the rate ofspecies immigration and, tions and caveats, and corridors designed for one thereby, the number ofspecies occupying the island speci®c function will serve other functions, perhaps =Willis, 1974; Wilson and Willis, 1975). unintentionally. Further, confusion arises because In metapopulation theory, individuals ofa single terms included in the de®nitions ofcorridor are often species are distributed among multiple patches of themselves loosely de®ned or the subject ofmisun- habitat Ð perhaps as a result ofhabitat fragmentation. derstanding and debate =e.g. dispersal, habitat). The dynamics ofa metapopulation are a function of In this paper, we review brie¯y the history ofthe within-population dynamics and among-population term `corridor' in the context ofconservation, catalog movement. Corridors enhance the ability ofindivi- some ofits de®nitions and uses, review the functions duals to move among habitat patches, lowering the ofcorridors, and differentiatebetween the structural expected time to recolonization ofa patch that has and functional aspects of corridors. We reject the suffered extinction. Emigrants from well-populated notion ofde®ning the term `corridor' succinctly, patches may also `rescue' patches with depleted because ofits widespread and varied use by people populations =Brown and Kodric-Brown, 1977). In G.R. Hess, R.A. Fischer / Landscape and Urban Planning 55 52001) 195±208 197 combination, these phenomenon are believed to and Forman =1995) identi®ed six societal goals corri- reduce the probability ofspecies extinction. dors contribute to corridors =Table 3). Use of`corridor' in game management, island The roles corridors play in addressing societal goals biogeography, and metapopulation literature focused derive from a number of ecological functions: habitat, on function, namely, the movement of¯ora and fauna. conduit, ®lter, barrier, source, and sink =Fig. 1; For- A structural use ofthe term arose in the ®eld of man and Godron, 1986; Forman, 1995; Smith and landscape ecology as it developed in North America. Hellmund, 1993; Dramstad et al., 1996). Forman and Forman and Godron =1981, 1986) introduced the Godron =1981, 1986) introduced discussion ofthese matrix±patch±corridor paradigm oflandscape struc- six ecological functions, along with their structural ture, in part because ofits utility in describing and de®nition ofcorridors. These functional roles are analyzing the structure oflandscapes as seen in aerial presented in a wide range ofconservation literature, photographs and satellite images =Forman, 1991). In from wildlife conservation to greenways and hiking this terminology, a matrix is the most extensive and trails. They have been widely adopted, including use most connected landscape type, a patch is a non-linear in a recent corridor planning manual produced by the surface area differing in
Load more

Recommended publications
  • A Bridge to the Future
    A Bridge To The Future BUILDING CALIFORNIA’S FIRST FREEWAY WILDLIFE CROSSING LIVING HABITATS/NWF AN LA STORY & A MODEL FOR THE WORLD COUGAR P-22 IN HIS UNLIKELY HOME... DEAR FRIENDS: THE MIDDLE OF In 2012, I read a news story about a mountain lion known as P-22, who miraculously crossed two of the busiest LOS ANGELES freeways in the country in order to find a new home in an unlikely place—the middle of Los Angeles. He has since become beloved by people around the world, yet he remains trapped and alone on a city island. His plight symbolizes the threats that all wildlife in the Los Angeles area face — freeways, roadways and development act as deadly obstacles for animal life. Research by the National Park Service has shown this local population of mountain lions will likely face extinction if we don’t act soon. THE GOOD NEWS? WE CAN SOLVE THIS. We welcome you in joining our dedicated community of supporters and philanthropists to build the wildlife crossing at Liberty Canyon. Once built, this crossing, which will be the largest in the world, will re-connect an entire ecosystem that has long been fragmented by an almost impenetrable barrier for wildlife—the 101 Freeway’s ten lanes of pavement and 300,000 cars a day. In my thirty years of advocating for wildlife, I’ve been fortunate enough to have worked in two of the largest national parks in the country, Yellowstone and Yosemite. Yet nothing has inspired me more than the chance to help build this landmark crossing in the most densely populated metropolitan area in the United States.
    [Show full text]
  • Wildlife Corridors LLC Preserving and Restoring Critical Habitat
    HABITAT CONNECTIONS Wildlife Corridors LLC: Preserving and Restoring Critical Habitat Linkages in the US-Mexico Borderlands The Wildlife Corridors property at Three Canyons Ranch near View of the Patagonia Mountains from Wildlife Corridors Property/ Patagonia, AZ is at the heart of a Laura Nolier swath of land identified by biologists as an essential migratory KEY ISSUES ADDRESSED route for many wildlife species, Linkages between undeveloped habitat are essential for including jaguars. It was once genetic flow and biodiversity of wildlife species. These slated to be a 189-lot, high-density linkages--often called wildlife corridors--are becoming housing development. Following increasingly threatened as human populations expand. the development’s bankruptcy, the Urbanization, agriculture, highways and other human property was purchased by local development have led to habitat fragmentation and the conservation group Wildlife overall disruption of migratory paths used by animals. Corridors LLC and affiliated The Wildlife Corridors property preserves a critical Borderlands Restoration with the corridor segment while managing for multiple uses and enjoyment by the surrounding communities. By involving intention of creating a single local communities in learning from and tending to their conservation easement covering local watershed, the property also serves to educate the the northern 80% of the property public about the importance of undeveloped spaces for within the mainstay of the wildlife wildlife movement. corridor. PROJECT GOALS • Strategic acquisition of land identified as an important habitat linkage for several wildlife species • Community engagement and education • Manage for moderate recreational use, ecological restoration, and wildlife corridor Project Location integrity “UN-DEVELOPMENT” The purchase of the Three Canyons Ranch property initiated the conversion of 189 housing lots and fragmented conservation easement into a wildlife-only corridor where human impacts remain minimal.
    [Show full text]
  • Jungle Cats Caught on Camera in Belize 17 May 2012, by Sarah Rakowski
    Jungle cats caught on camera in Belize 17 May 2012, By Sarah Rakowski Today, the only protected broadleaf forest link between Maya Mountains and the forested coastal plains falls within the 320,000 acre Maya Golden Landscape. This remaining wildlife corridor is particularly important for jaguars and other large mammals (such as tapirs and peccaries), as it allows cross-breeding between two increasingly isolated populations. Ya'axché Conservation Trust (Fauna & Flora International's partner in Belize) is working hard to protect the Maya Golden Landscape by engaging with the communities, farmers and private landowners living in and around the Maya Golden A jaguar prowls past the camera. Credit: Maarten Landscape. Hofman/Ya'axché Conservation Trust. To help ensure that Ya'axché's conservation work really benefits biodiversity in the area, the ranger A camera trap survey, set up by scientists from team set up a number of camera traps (automatic, Ya'axché Conservation Trust, has caught pictures motion-detecting cameras, supplied by IdeaWild) in of Central America's two big cats: the jaguar and the area, to help them learn more about which the puma (known locally as the red tiger). species inhabit the corridor. Both species are threatened by habitat loss and In addition to jaguar and puma, the cameras have unsustainable hunting of their prey, and it is captured images of red brocket deer, possum, thought that only around 250-400 jaguars now great currasow, white-lipped and collared peccary remain in the Maya Mountains. and agouti - all of which are prey species for the jaguar and puma.
    [Show full text]
  • Saving Habitats Saving Species Since 1989 Inside This
    WLTnews ISSUE No. 59 AUTUMN 2018 Inside this issue: • Save Jungle for Jaguars in Belize • Donations doubled in Big Match Fortnight • 400 acres saved in Amazonian Andes • New project in Colombia Saving habitats Saving species since 1989 Sponsored by worldlandtrust.org 2 Donations between 3-17 October will be matched Saving land for Belize’s Jaguars We’re raising £600,000 to protect 8,154 acres of Jungle for Jaguars Belize’s Jaguars are still under threat. We need your help to protect their home and ensure the future of this vital habitat, creating a corridor of protected areas in the northeast of the country. 30 years on from World Land Trust’s very first project in Belize, we are returning to embark on one of our most ambitious projects yet. Saving highly threatened but wildlife- rich habitats from deforestation in Belize is even more urgent now than it was 30 years ago. In the past 10 years, 25,000 acres of wildlife habitat has been cleared for agriculture and development in northern Belize, and we need to create a corridor to ensure the connectivity of one of the few pieces of habitat left to Jaguars and other wildlife in the region. We must act now. By supporting this appeal today, you will be saving this jungle for Jaguars, Endangered Baird’s Tapir, and other key species including Nine-banded Armadillo, Keel-billed Toucan and Ornate Hawk-Eagle. If this land is not purchased for conservation and protected by our partner, Corozal Sustainable Future Initiative (CSFI), this habitat will be fragmented and we will have missed the last opportunity to create a corridor for Belizean wildlife that connects the natural and rare habitats in the northeast of the country with existing protected areas in the south.
    [Show full text]
  • Wildlife Corridors Around Developed Areas of Banff National Park
    WILDLIFE CORRIDORS AROUND DEVELOPED AREAS OF BANFF NATIONAL PARK WINTER 1996/1997 QH By 541.15.C67 1 W542 . Karsten Heuer 1997 Rhonda Owehar C1 Danah Duke Sheila Antonation FEBRUARY 10, 1998 1. Ecology Base Research, Box 1053, Banff, AB, Tal oeo REFERENCE -<fit ~ I Canadian Heritage ~j I T Parks Canada Almra ~~--~~ ENVIRONMENTAL PROTECTION BOW VALLEY NATURALISTS A TransAlta Utilities Canadian Parks and Town of Wilderness Society CANMORE Wildlife Corridors in BNP 1996/97 Karsten Heuer February 1998 Ecology Base Research Box 1053 Banff, Alberta TOlOCO This project was conducted under the terms of Parks Canada contract #X60036. The views expressed are those of the authors and do not necessarily reflect the policies of Parks Canada. Funding was provided by Parks Canada, Bow Valley Naturalists, Canadian Parks and Wilderness Society, Castle Mountain Village, Friends of Banff National Park, Kananaskis Country, TransAlta Utilities and the Town of Canmore, Readers should refer to Heuer (1995) for a recent literature review on wildlife corridors and habitat fragmentation and Heuer (1995), Stevens et al (1996) and Stevens and Owchar (1997) for progress reports on previous years' wildlife corridor monitoring in Banff National Park. This dqcument may be cited as: Heuer, K., Owchar, R., Duke D. and S. Antonation. 1998. Wildlife Corridors around Developed Areas of Banff National Park. Progress Report, Winter 1996/97. 46pp. LIB AS (403) 162.,.1 • Ecology Base Research Box 1053, Banff, Alberta TOL OCO Wildlife Corridors in BNP 1996/97 ii TABLE OF CONTENTS
    [Show full text]
  • Wildlife Corridors 15 15
    NORTH EAST NEW SOUTH WALES Wildlife Corridors 15 15 What are wildlife corridors? pollination of plants and other natural functions required for ecosystem health. A wildlife corridor is a link of wildlife The likely result is severe biodiversity habitat, generally native vegetation, which decline and local extinction of sensitive joins two or more larger areas of similar species. wildlife habitat. Corridors are critical for NOTE the maintenance of ecological processes Corridors play an extremely important role NOTE including allowing for the movement of in the maintenance of biodiversity, but they animals and the continuation of viable can only partly compensate for the overall populations. habitat loss produced by the fragmentation of the natural landscape. It is important, By providing landscape connections therefore, that vegetation remnants and between larger areas of habitat, corridors vegetated corridors are maintained and enable migration, colonisation and enhanced as a network across all lands interbreeding of plants and animals. both private and public. In this way private Corridors can consist of a sequence of landscapes can contribute to wider stepping stones across the landscape landscape conservation efforts by (discontinuous areas of habitat such as enhancing and linking existing reserves paddock trees, wetlands and roadside and conservation networks. vegetation), continuous lineal strips of vegetation and habitat (such as riparian NPWS Geoff Biddle/ strips, ridge lines etc.), or they maybe parts of a larger habitat area selected for its known or likely importance to local fauna. Why are corridors important? Habitat loss and fragmentation are the two main contributors to continuing biodiversity Aerial photograph showing the importance decline across the landscape.
    [Show full text]
  • A Wildlife Corridor Is a Link Of
    Land for Wildlife Queensland: Note G2 Wildlife Corridors wildlife corridor is a link of Why are corridors important? vegetation that joins two or A Wildlife corridors: more areas of habitat. Often referred • Allow the movement of birds, reptiles, mammals, frogs, invertebrates, plant to as ‘linkages in the landscape’, seeds and fungal spores. corridors play an important role in the • Provide habitat for migratory and resident wildlife. maintenance of ecological processes. These landscape connections • Provide refuge for wildlife that use nearby limited-value habitat such as open enable migration, colonisation and paddocks. interbreeding of plants, animals • Allow species to re-colonise patches of vegetation. and fungi. This Note explores the • Enable the exchange of genes between wildlife populations and reduce the attributes and values of corridors and possibility of inbreeding. identifies ways in which landholders • Maintain species richness at patch and landscape scales. can maintain, enhance or re-create • Can help maintain ecosystem processes such as pollination. corridors on their properties. Habitat loss and fragmentation are the two main contributors to continuing biodiversity decline across the landscape. When native vegetation is cleared, fragmented patches or islands of vegetation are created resulting in the isolation of many plant and animal species. This in turn reduces the viability of ecosystems and the populations of species within them. Ultimately, this can result in severe biodiversity decline and local extinctions. Taking a landscape view across both public and private lands can highlight where wildlife corridors are required to re- connect fragmented patches of vegetation. Types of corridors Corridors are often categorised according to scale and can range from national significance, with corridors being many kilometres wide, to a property scale corridor that may only be less than 20 metres in width.
    [Show full text]
  • Wildlife Corridors Master Response 3
    4.0 MASTER RESPONSE 3- WILDLIFE CORRIDORS MASTER RESPONSE 3 – WILDLIFE CORRIDORS This master response addresses comments on the RDEIR related to wildlife corridors, and the project’s potential impacts on such corridors. The primary comments related to this issue are found in letter RD-12 (Big Sur Land Trust), as well as Letter RD-2 (California Department of Fish and Wildlife), and RD-14 (LandWatch Monterey County). As the Big Sur Land Trust (BSLT) letter (together with attachments from Pathways for Wildlife) is devoted entirely to the RDEIR’s treatment and analysis of wildlife corridors, the following responses generally correspond to that letter. 1. Wildlife corridor definition. The definition of a wildlife corridor used in the RDEIR is consistent with the definition related to conservation ecology. The term corridor refers to the area that is used by organisms to move between patches of suitable habitat (Soule and Gilpin 1991; Hilty et al. 2006). As its name implies, it is a connection between areas of suitable habitat such that it provides connectivity for plants and animals to exchange genes through movement between those areas (Crooks and Sanjayan 2006). In a review of the terminology, Meiklejohn, Ament, and Tabor (2009) reported that all definitions for wildlife corridors referred to the regions of the landscape that facilitate the flow or movement of individuals, genes, or ecological processes. A draft white paper (Western Governors’ Association 2009) calls for standardization of data and definitions so connectivity analyses can be performed across state boundaries. The definition identified in the white paper states that “wildlife corridors are crucial habitats that provide connectivity over different time scales (including seasonal or longer), among areas used by animal and plant species…and serve to maintain or increase essential genetic and demographic connection of populations.” This is consistent with the terminology used in the RDEIR.
    [Show full text]
  • Nchrp Synthesis 305
    NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM NCHRP SYNTHESIS 305 Interaction Between Roadways and Wildlife Ecology A Synthesis of Highway Practice CONSULTANT GARY L. EVINK Ecologist Tallahassee, Florida TOPIC PANEL GREGG ERICKSON, California Department of Transportation PAUL GARRETT, Federal Highway Administration MARY E. GRAY, Federal Highway Administration ALEX LEVY, Federal Highway Administration JOEL MARSHIK, Montana Department of Transportation PATRICK MCGOWEN, Western Transportation Institute PAUL J. WAGNER, Washington State Department of Transportation JON WILLIAMS, Transportation Research Board SUBJECT AREAS Energy and Environment, and Safety and Human Performance Research Sponsored by the American Association of State Highway and Transportation Officials in Cooperation with the Federal Highway Administration TRANSPORTATION RESEARCH BOARD — THE NATIONAL ACADEMIES WASHINGTON, D.C. 2002 www.TRB.org NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM NCHRP SYNTHESIS 305 Systematic, well-designed research provides the most effective Project 20-5 FY 2000 (Topic 32-11) approach to the solution of many problems facing highway ad- ISSN 0547-5570 ministrators and engineers. Often, highway problems are of local ISBN 0-309-06923-8 interest and can best be studied by highway departments indi- Library of Congress Control No. 2002111522 vidually or in cooperation with their state universities and others. © 2002 Transportation Research Board However, the accelerating growth of highway transportation de- velops increasingly complex problems of wide interest to high- way authorities. These problems are best studied through a coor- Price $16.00 dinated program of cooperative research. In recognition of these needs, the highway administrators of the American Association of State Highway and Transportation NOTICE Officials initiated in 1962 an objective national highway research program employing modern scientific techniques.
    [Show full text]
  • Belize Wildlife Corridor
    F R E E Connecting Landscapes across the Belize Wildlife Corridor February 2018 My Beautiful Belize, A Visitor’s Guide - San Pedro, Ambergris Caye, Belize Page 1 From the Editor Tamara Sniffin IN THIS ISSUE: Passion fuels inspiration, and one of the Preserving Belize’s Wildlife Corridor: best things about inspiration is how darn Did you know Belize’s corridor is the only connection between contagious it can be! Just a little bit can northerly and southerly forests at this latitude anywhere from the brush off and the next thing you know you Atlantic to the Pacific? P. 3 are infected in a GOOD way! In keeping with Que Viva Carnaval: our 2018 theme of conservation, our My In a riot of color, music and dance, alongside splatters of paint, Beautiful Belize issue this month is brimming San Pedro Town’s Carnaval is set for February 11th - 13th. P. 6 with stories that not only inspire you to care The man, the myth...the legend: about preservation, but about others who People from all walks of life can make a difference in the world. have committed their lives to it, infecting us Belize is blessed to count Roni Martinez, birding extraodinaire, with their passion along the way. Even our article about coconut oil emphasizes using every part of the nut, from the water to the husk, among this elite crowd. P. 11 and we learn that this tropical resource is the gift that just keeps on We’re nuts for Coconuts: giving. This lesson can inspire us to find ways not to waste parts of a Learn how to make your own coconut oil, which will bring resource that could be utilized somehow…heck, coconut husks even home a taste of Belize to your kitchen! P.
    [Show full text]
  • Use of Highway Undercrossings by Wildlife in Southern California
    Biological Conservation 115 (2004) 499–507 www.elsevier.com/locate/biocon Use of highway undercrossings by wildlife in southern California Sandra J. Nga,b, Jim W. Dolea, Raymond M. Sauvajotb,*, Seth P.D. Rileyb, Thomas J. Valonec aDepartment of Biology, California State University, Northridge, CA 91330-8303, USA bNational Park Service, Santa Monica Mountains National Recreation Area, 401 West Hillcrest Drive, Thousand Oaks, CA 91360, USA cDepartment of Biology, St. Louis University, St. Louis, MO, USA Received 13 June 2001; received in revised form 15 February 2003; accepted 20 March 2003 Abstract Roads, especially large highways, can have significant impacts on wildlife movement and survival. This is especially true for wide- ranging species, such as mammalian carnivores. Some of these impacts may be mitigated if wildlife can find and utilize passageways under highways. To determine if underpasses and drainage culverts beneath highways are used by wildlife as movement corridors, we monitored 15 such passages near Los Angeles, California using remotely triggered cameras and gypsum track stations. We found that passages were used by a variety of species, including carnivores, mule deer, small mammals, and reptiles. Many types of undercrossings were utilized, indicating that passages beneath highways, even when not originally designed for wildlife, can provide important safe avenues for animals to cross roads. For mammals of conservation concern, including native carnivores and deer, passage dimensions, surrounding habitat, and the extent of human activity were assessed to determine if these factors influenced passage use by these species. Our results show that while many native mammals used passages beneath highways, the presence of suitable habitat on either side of the passage was a particularly important factor predicting use.
    [Show full text]
  • Background-Brief-Wildlife-Corridor
    WILDLIFE CORRIDORS LPRO: LEGISLATIVE POLICY AND RESEARCH OFFICE BACKGROUND BRIEF Oregon’s natural environment is home to several large- bodied animals such as elk, mule deer, and pronghorn TABLE OF CONTENTS antelope. These animals, along with many other ECONOMIC OVERVIEW OF species, rely on migration routes for access to food, WILDLIFE CORRIDORS 1 water, and shelter across the seasons. Landscapes surrounding migration routes often experience change FEDERAL & STATE ACTION ON due to human population growth and associated WILDLIFE CORRIDORS 4 residential, commercial, and transportation OREGON WILDLIFE CORRIDOR development. Changes in land use create obstacles in INITIATIVES 6 existing migration corridors, leaving animals isolated and vulnerable. Wildlife corridors, which are pathways of undeveloped land connecting one area of habitat to another, provide safe passage for animals needing to navigate a fragmented ecosystem. This brief serves as a broad overview of the current state of wildlife corridors, both state-based and nationwide. The next section provides a general economic overview of wildlife corridors, including a look at Oregon’s road network and wildlife-vehicle collision numbers, and is followed by a review of existing federal and state action on wildlife corridors. The brief concludes with a summary of Oregon’s current initiatives on wildlife corridors. ECONOMIC OVERVIEW OF WILDLIFE CORRIDORS The National Wildlife Federation recognizes that one of the best ways to protect animal habitats and boost biodiversity is to keep landscapes connected.1 Similarly, the Oregon Department of Fish and Wildlife (ODFW) finds that habitat connectivity is key to managing not only terrestrial animals but aquatic and avian species, as well.
    [Show full text]