Desperately seeking stable 50-year-old Paul Beier and Andy Gregory, Northern Arizona University landscapes with long, wide corridors

Do conservation corridors really work? (“It depends.”) What are the traits of successful conservation corridors? Paul Beier and Andy Gregory, Northern Arizona University

For 10 years, I’ve been designing corridors for focal species so we can conserve them... A B … before we develop the rest of the matrix.

South Coast Missing Linkages: 11 designs Over 240,000 acres conserved

Arizona Missing Linkages  16 Linkage Designs are being implemented (e.g., these wildlife crossings near Tucson)

Bay Area Critical Linkages: 14 designs California Desert Connectivity: 23 designs

I’ve helped develop 64 Linkage Designs since 2001 The good news: These plans are being implemented! The scary question : “Will these corridors work? ”

Each corridor design is a prediction: These long swaths of land will support gene flow between the two wildland blocks even after the matrix land has been converted to uses incompatible with wildlife movement. Do conservation corridors work?

But… don’t we already know that corridors work? Gilbert-Norton et al. (2011. Conservation Biology 24: ) summarized 78 corridor experiments: Corridors increased movement between patches by 50% on average.

length ½ to 100 km width > 1 km matrix: cities, farms desired response: long-term gene flow; patch occupancy Conservation corridor length < 150 m width < 100 m matrix: natural land cover measured response: animal movement Typical corridor study 1-ha clearcut patches connected by 150 x 25 m corridor within forest (Savannah River Ecology Lab) Past research does not tell us whether conservation corridors work.

Let’s find & study 100 “de facto” conservation corridors – anywhere on Earth. Criteria: Sampling locale 2. Matrix is human-dominated non-habitat. 3. Focal species: any flightless mammal, reptile, amphibian, or arthropod that avoids matrix. 4. At least ½ km between patches 5. At least one type of reference: Isolated patches, or 1. Stable landscape for decades (long enough for landscape pattern to produce a genetic signal) Intact area as big as corridor plus linked patches Cities, suburbs, row crops >½ km

Genetic distance between patches connected by a corridor was high – just as high as between isolated patches.  … and much higher than between sampling areas within intact habitat.  Horskins et al (2006): the corridor failed. Cities, suburbs, & row crops CP 1 CP 2 SL 2 SL 1 IP 2 IP 1 >½ km Connected patches Isolated patches Samples in intact area Genetic distance

Genetic distances between 3 pairs of patches connected by corridors were lower than between isolated patches. … but much higher than between sampling areas within intact habitat.  Mech & Hallett (2001): the corridors worked - ? Cities, suburbs, & row crops CP 1 CP 2 SL 2 SL 1 IP 2 IP 1 >½ km Connected patches Isolated patches Samples in intact area Genetic distance

A large sample will show: 1. That some corridors do promote gene flow at the same levels as intact landscapes, and other corridors fail. 2. Which factors are associated with corridors that work. n = 1 Landscapes = replicates Desperately seeking stable 50-year-old landscapes with long, wide corridors Cities, suburbs, & row crops >½ km

Learn more or suggest landscapes at Desperately seeking stable 50-year-old landscapes with long, wide corridors Cities, suburbs, & row crops A B Z Y N M >½ km $250 honorarium for sites we use Ask your friends to find us on Facebook.

Focal Species Any species that uses the habitat patches and the corridor but not the matrix Species with short generation times and smallish N e are preferred

Current status & project update June 2011, project initiated 0, study sites July 2011, Launched our website and sent out a mass plea for site suggestions September - November 2011, Second mass and publication of plea for study sites in Frontiers, BES, and other professional organization blogs and news letters As of 19-January 2012:  Website has had >1,500 visits, from >80 countries  38 landscapes meeting criteria (subject to ground- check): US, Germany, Netherlands, Poland, Uganda, India, Kenya, Ethiopia, South Africa, Costa Rica, Brazil, Argentina, & Sabah Borneo. WE STILL NEED >60 MORE SITES….. WE ARE STILL DESPERATE

A corridor design is a prediction that “this land will support gene flow between the two wildlands even after the other matrix land has been converted to uses incompatible with wildlife movement.” If we want to test this prediction, we must study gene flow in landscapes where the corridors are of similar size as conservation corridors, and where the matrix has been converted. “This project is the most important thing that could be done in the study of corridors, and one of the top 3 most important things that can be done in all of conservation biology.” - Dr. Nick Haddad, NC State University