RESTORING LANDSCAPE CONNECTIVITY IN A CHANGING WORLD

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: TERMINATED
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 0226631
• Project No.: NC02376
• Project Start Date: Oct 1, 2011
• Project End Date: Jul 1, 2013

Project Director
Haddad, N.

Recipient Organization
NORTH CAROLINA STATE UNIV
(N/A)
RALEIGH,NC 27695

Performing Department
Biology

Non Technical Summary
Landscape corridors are the most popular strategy for landscape scale conservation where habitat has been lost or fragmented. Research in the Haddad lab investigates whether corridors will work. Specifically, his group will test whether corridors serve as superhighways for plants and animals, increasing their ability to migrate across human-dominated landscapes. We will also test whether corridors have impacts on populations and communities of plants and animals. His groups work in restoration will test the value of landscape approaches for restoration of species in dire need of conservation, including on the rarest butterflies. His lab's work will further the conservation of biodiversity in a rapidly changing world.

Animal Health Component

0%

Research Effort Categories

Basic

100%

Applied

(N/A)

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
136	0611	1070	20%
136	0850	1070	40%
136	0860	1070	40%

Knowledge Area
136 - Conservation of Biological Diversity;

Subject Of Investigation
0850 - Wildlife habitats; 0611 - Conifer forests of the South; 0860 - Endangered species;

Field Of Science
1070 - Ecology;

Keywords

biodiversity

conservation

corridors

butterflies

source-sink

population ecology

community ecology

connectivity

landscape ecology

restoration

climate change

Goals / Objectives
Habitat loss and fragmentation are the most important threats to biodiversity, and these threats are exacerbated by climate change. Research in the Haddad lab seeks to understand these threats, and, more importantly, to test conservation strategies that reduce them. Work in the lab focuses centrally around the role of landscape corridors - long, thin strips of habitat - that reconnect landscapes where habitat has been degraded and fragmented. Haddad's group has made great advances in our understanding of the role of corridors, and, according to one recent review, we have accounted for over 40% of all research on corridors. What is needed now is to understand the consequences of corridors for the conservation of populations, and in the context of a changing world. To accomplish these objectives, Haddad's research will have three foci. First, Haddad's lab will continue to spearhead research on corridors in experimental landscapes at the Savannah River Site, SC. Within those landscapes, we will accomplish three objectives in the coming five years: 1) corridors are meant to serve as superhighways for plants and animals, yet we do not know for how many species corridors actually work. We will use new technologies to track dispersal of communities of plants and insects. 2) Corridors are ultimately created to increase gene flow and population persistence. Our experiments have been established for 12+ years (dozens of insect generations), and we can determine with corridors have affected population genetic structure. And, 3) Our experiments have been established long enough to influence the persistence of populations and biodiversity, and we will determine the effects of corridors through long-term monitoring of plant populations. Second, to complement research from our experiments, we will conduct research on populations of rare butterflies. For these butterflies, habitat loss is a key threat, and habitat restoration (including restoration of landscape connectivity) is a key means to preserve the butterflies. Our research encompasses two rare butterflies in North Carolina, and a number of rare butterflies in south Florida. We will conduct tests of key threats to butterflies, and develop strategies to overcome key threats. Along the way, we will develop rigorous approaches to population monitoring for rare butterflies. Third, we will conduct experiments to test landscape approaches to restoration for rare butterflies. Many butterflies depend on complex environmental dynamics, maintained by disturbance, for their populations to thrive. These dynamics include fire or inundation, and the same disturbances that maintain habitat can also eliminate populations. We propose to test whether we create actual habitat using disturbance, and specifically whether restoration creates population sources (where populations are growing) or sinks (where populations are shrinking). Further, we will work with collaborators to conduct parallel experiments for different butterfly species and to create general approaches to restoration management in a landscape context.

Project Methods
A. Dispersal In 2000, we created eight large-scale experimental landscapes (hereafter "blocks") at the Savannah River Site (SRS), South Carolina that explicitly test for connectivity effects while controlling for patch area and shape. We will conduct dispersal studies on 25 focal plant species that vary in dispersal mode, seed size, and terminal velocity. All are common at our study sites in longleaf pine savanna. Similarly, we have selected 25 focal arthropod species, representing major groups of mobile insects commonly found in longleaf pine savanna at SRS. These species vary widely in body size. Dispersal of all organisms will be measured by 15N-tagging, a simple, cost-effective technique already validated under field conditions. B. Population genetics We will collect 10 individuals of each species from Savannah River Site, but not from our experimental landscapes, for use in marker development and optimization. We will then collect tissues from wing fragments of 30 individuals of each species within each patch. Individuals will be collected by sweep netting. We will measure the wing length, body length, and thoracic width of 50 butterflies of each species for use in trait analysis. Microsatellites are the marker of choice for testing our predictions because they are highly variable, widespread in the nuclear genome of most taxa, co-dominant, and typically selectively neutral or nearly neutral. Most important, the high levels of allelic variation in microsatellites provide the power needed to examine patterns of genetic variation in small populations with reduced genetic variation. We will take advantage of next-generation sequencing to develop microsatellite markers for each of our species. C. Restoring Population Sources for Rare Butterflies We will employ two methods of de novo habitat restoration for St. Francis' satyr butterfly: hardwood removal and wetland creation. A key advantage of implementing restoration as part of this project is that we can design restoration as a factorial experiment in a completely blocked design to control for landscape effects. We will restore SFS habitat first by removing hardwood trees to retard wetland succession. We will also restore St. Francis' satyr habitat by damming streams to create wetlands, then reduce or remove dams to permit sedge development. Although we have not previously created such dams, we do know of several St. Francis' satyr populations that have formed where dirt roads have blocked streams (and culverts have been dammed by beavers). We will four blocks, each containing the four treatment combinations (with or without hardwood removal, with or without inundation). We will initiate populations at all restored sites by introducing captive reared individuals. We will obtain eggs from wild caught females, who readily lay eggs in oviposition chambers. We will then rear caterpillars on potted sedges, with a 50% success rate of raising eggs to adults. We will release these captive individuals to all of our experimental sites. We will measure adult survival and population size in each restored site using mark-recapture methods.

Progress 10/01/11 to 07/01/13

Outputs
Target Audience: My target audience is other scienists, as well as conservationists and land manager who protect native habitat. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? The project has provided opportunities for training of two postdocs and four graduate students. Postdocs have worked to implement large restoration experiments for butterflies, and to measure demographic responses. Graduate students have 1) tested effects of habitat fragmentation and climate change on biodiversity; 2) tested effects of climate change on butterfly phenologies; 3) tested effects of landscape corridors on predators; and 4) tested the effects of corridors on butterfly genetics. How have the results been disseminated to communities of interest? In addition to peer reviewed publications, students and postdocs have all given talks at national meetings (Ecological Society of America, Society for Conservation Biology). We have also created a website ConservationCorridor.org to translate scientific results for land managers. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? In 2013, we completed data collection of wind dispersed seeds and arthropods in experimental landscapes. These data will be used to understand how landscape corridors influence the dispersal of communities of organisms. We also developed new monitoring techniques for rare butterflies, including approaches based on remotely sensed data, and based on methods for point counts of butterflies to estimate their densities.

Publications

• Type: Journal Articles Status: Published Year Published: 2013 Citation: Wilson, J.W., J.O. Sexton, R.T. Jobe, and N.M. Haddad. 2013. The relative contribution of terrain, land cover, and vegetation structure indices to species distribution models. Biological Conservation 164:170176
• Type: Journal Articles Status: Published Year Published: 2013 Citation: Mata, T.M., N.M. Haddad, and M. Holyoak. 2013. How invader traits interact with resident communities and resource availability to determine invasion success. Oikos 122: 149160

Progress 10/01/11 to 09/30/12

Outputs
OUTPUTS: In 2012, Haddad and his students have conducted numerous activities related to the effects of landscape change on conservation of rare animals, on dispersal, and on biodiversity. In his experimental research at Savannah River Site, Dr. Haddad has maintained the world's largest and longest running experiment dedicated to understanding the effects of habitat fragmentation and corridors. Haddad and his lab continued their research to understand the role of corridors in restoration. Haddad's team has implemented a massive and innovative experiment to test the role of corridors in promoting dispersal across entire communities of plants and animals. The new technique is to label plants (and then through their consumption of plants, higher trophic levels) with heavy isotopes of nitrogen. By capturing seeds and insects and evaluating the concentration of heavy nitrogen, we can specify the dispersal process over many species that disperse long distances. Haddad's students have also made progress in assessing the effects of corridors on genetic population structure of butterflies, and on the population and food web dynamics of predators (in this case spiders). Haddad has expanded his assessment of landscape connectivity as an adaptation to climate change in the southeastern US. He obtained a grant through the SE Climate Science Center to bring together a group to determine how landscape connectivity can be best conserved in the southeastern US. He convened a meeting of the Landscape Conservation Cooperatives to determine targets for connectivity analysis in 2013. Haddad continued long-term studies on the conservation and management of endangered and threatened animals, including the St. Francis' satyr and Miami blue butterflies, and restoration geared at protecting these rare species. For St. Francis' satyrs, his group implemented a large new restoration experiment to test how two different restoration techniques, including hardwood removal and dam creation, influence habitat quality. In particular, we are asking whether restoration creates population sources (positive population growth) or sinks for rare species. He continues to develop methods for restoration and recovery, including improvement of captive rearing of caterpillars. In his work on Miami blue butterflies, he is creating new plans for monitoring populations of this remote and very rare species. Haddad also advanced understanding of how loss of biodiversity at one trophic level cascades through the foodweb, and affects other trophic levels. He continued to assemble a large and long-term dataset on insects from the world's largest experiment to manipulate levels of biodiversity. He performed data analyses and writing to assess effects plant phylogentic diversity, and measure that integrates the evolutionary differences among species, to predict diversity and abundance of arthropods. Haddad created a new website, www.ConservationCorridor.org, to connect scientists and manager that use corridors in conservation planning. The goal of the website is to promote the latest science and the latest conservation innovations, and bring together scientists and practitioners. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Scientists, state and government agencies, and conservation practitioners PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
At Ft. Bragg, Haddad's group made two advances. First, his postdoc showed that riparian forest habitats along streams can serve as corridors connecting populations of St. Francis satyrs within wetlands (Milko, et al. 2012). St. Francis' satyrs live in isolated populations within habitats created by beavers that abandon their ponds, allowing wetlands to form. It has long been thought that riparian habitats form corridors, and this genetic study showed that, plus that human created barriers such as roads can impede dispersal. Additionally, we found that behaviors of butterflies observed while moving can predict dispersal between habitats (Hudgens, et al. 2012). These results showed how behavioral studies can be used to site new restoration areas where dispersal is unknown, and showed that detailed and costly behavioral studies may be useful in improving understanding of dispersal. We applied new measures of species diversity, phylogenetic diversity, to understand how plant diversity affects the diversity and abundance of insects. Two exciting aspects of this study were that 1) one measure of phylogenetic diversity was completely independent of the traditional measure, plant species richness (the number of plant species), and 2) that these two measures used together in a statistical model could predict over half the variation in insect diversity. This is the strongest test yet to show that insect diversity is determined by plant diversity. We launched www.ConservationCorridor.org, a new resource of the conservation community.

Publications

• Hudgens, B.R., W.F. Morris, N.M. Haddad. W. Fields, J. Wilson, D.C. Kuefler, and R.T. Jobe. 2012. How complex do models need to be to predict dispersal of threatened species through matrix habitats Ecological Applications 22:1701-1710.
• Milko, L.V., N.M. Haddad, and S.L. Lance. 2012. Dispersal via stream corridors structures populations of the endangered St. Francis' satyr butterfly (Neonympha mitchellii francisci). Journal of Insect Conservation 16:263-273.
• Haddad, N.M. 2012. Connecting ecology and conservation through experiment. Nature Methods 794-795.
• Dinnage, R., M.W. Cadotte, N.M. Haddad, G.M. Crutsinger, and D. Tilman. 2012. Diversity of plant evolutionary lineages promotes arthropod diversity. Ecology Letters 15:1308-1317.