EVALUATION OF THE CONSERVATION LANDS OF MAINE BASED ON PRESENCE OF HABITAT SUITABLE FOR LISTED SPECIES

Michael Ambrogi ‘09 and Kimberly Bittler ‘11

Colby College: Environmental Studies Program

Abstract

“Conservation Lands” include both public and private lands that are devoted to the protection of wildlife and natural resources. “Listed Species” include federally and state endangered and threatened animals that are in danger of extermination in the state of Maine. The purpose of this study is to determine how well conservation lands are protecting the habitats of listed species. GAP data was used for 13 terrestrial vertebrate species indicating the presence or absence of suitable habitats. This data was compiled in GIS, generating a layer showing the number of listed species an area is suitable for. The areas that were suitable for at least one habitat were compared to answer three questions: (1) Is there is a difference between the presence and absence of listed species on protected lands and lands that are not protected? (2) Is there is a difference between the presence and absence of listed species on public lands managed by the state and the federal government and private land? (3) Is there is a difference between the presence and absence of listed species on lands protected under easements and lands that are protected fee simple? We found significant differences between all three categories. Conservation lands, private lands, and lands held under easement protect the habitat of listed species most effectively. We believe that this is due to the large number of private land trusts in the state of Maine and the effective management strategies of state lands.

Introduction

“Conservation Lands” refer broadly to both public and private lands that serve as areas devoted to the protection of wildlife. There are several designations of conservation lands, each offering varying degrees of protection. Public lands are owned by state, federal or municipal governments and include areas such as wildlife management areas and parks. Private lands are held by individuals or groups such as land trusts or non governmental organizations. Land can be held under different types of agreements that restrict activities such as development or resource extraction.

Since conservation lands are typically protected from development, they have the potential to be important sanctuaries for wildlife. Species that are most at risk of extinction are designated as either endangered or threatened at both state and federal levels. Federally endangered species are designated by the Fish and Wildlife Service and protected under the Endangered Species Act. This protects species from “taking” which includes harassing, killing and trafficking individuals. This legislation also mandates that FWS create a Recovery Plan and allows FWS to designate critical habitats for each species listed. (1). Maine State Endangered species were previously determined by the legislature and reviewed every 5 years, but are now listed at the discretion of the Maine Department of Natural Resources. This legislation gives the state the authority to create programs for the conservation of listed species which includes the ability to acquire lands where the species are found. In order to transplant a species into a new area in a reintroduction, a recovery plan must first be made (2).

Areas of suitable habitat that correspond with conservation areas may be prime areas for focusing conservation efforts of transplanting, federal and state recovery plans. This also serves as an indicator of the effectiveness of conservation lands of Maine protecting the most vulnerable species’ habitat. The different levels of protection are also compared to determine if certain programs and incentives are more effectively protecting listed species. The purpose of this study is to determine if conservation lands are effectively protecting the habitats of the most vulnerable species, which has implications for both state and federal recovery plans.

Methods

ESRI’s ArcGIS was used to analyze and map the data for this study, based off of two primary data sets: GAP data and Conservation Lands from the Maine office of GIS. The GAP data is binomial raster data, where a value of 1 is assigned to areas where habitat is suitable for a species, and a value of 0 is assigned to unsuitable habitat. The GAP data layers of 13 federally and state listed terrestrial vertebrates (Table 1) which had current data available were compiled. The raster layer generated in this process is the Habitat Value, which is the number of listed species that each cell is suitable for. The conservation lands layer is a vector layer that delineates conservation lands bases on state, federal and private ownership, as well as whether the land is held under a lease, easement, or owned fee simple. Areas covered by water bodies, determined by a ponds layer from the Maine Office of GIS, were erased from both layers.

Information from the Habitat Value layer was extracted by mask using the Conservation Lands layer for the analyses. The number of cells of each Habitat Value (0-6) for each independent variable (type of conservation land) were counted, and the differences tested for significance with the chi-square test. We focused on three null questions:

• Is there is a difference between the presence and absence of listed species on protected lands and lands that are not protected?

• Is there is a difference between the presence and absence of listed species on public lands managed by the state and the federal government and private land?

• Is there is a difference between the presence and absence of listed species on lands protected under easements and lands that are protected fee simple?

Table 1: List of terrestrial invertebrates used in the analysis and their conservation status.
Scientific Name	Common Name	Status
Clemmys guttata	Spotted Turtle	Maine-Threatened
Emydoidea blandingii	Blanding’s Turtle	Maine-Endangered
Terrapene carolina	Eastern Box Turtle	Maine-Endangered
Coluber constrictor	Racer	Maine-Endangered
Synaptomys borealis	Northern Bog Lemming	Maine-Threatened
Lynx canadensis	Canada Lynx	Federal-Threatened
Aquila chrysaetos	Golden Eagle	Maine-Endangered
Falco peregrinus	Peregrine Falcon	Maine-Endangered
Bartramia longicauda	Upland Sandpiper	Maine-Threatened
Chlidonias niger	Black Tern	Maine-Endangered
Cistothorus platensis	Sedge Wren	Maine-Endangered
Anthus rubescens	American Pipit	Maine-Endangered
Ammodramus savannarum	Grasshopper Sparrow	Maine-Endangered

Results and Discussion

Conservation Status

Non-conservation lands contained a significantly different percentage of land where listed species are absent and present compared to conservation lands (Figures 1, 2). Non-conservation lands contained a higher percentage of land that was unsuitable for protected species, with a habitat value of 0, than conservation lands. Conservation lands protected a higher percentage of lands with habitat values of 1 through 3. Therefore, the null hypothesis that there is no difference between the presence and absence of listed species on conservation and non conservation lands is rejected (p < 0.001).

The abundance of the areas with habitat values of 4 and 5 are so low they do not account for a significant portion of any land designation. Even if all land with habitat values of 4 and 5 occurred on conservation lands, these lands would account for only 0.6% of the total area of conservation lands.

Public versus Private

Privately owned land contained a greater percentage of its area suitable for listed species (Figures 3, 4). Public land contained a greater percentage of area where protected species are absent. Therefore, the null hypothesis that there is no difference between the presence and absence of listed species on lands owned privately and publicly was rejected (p < 0.001). However, public land has a higher percent of land containing 2 to 3 protected species compared to private lands. This may be a result of government-led conservation efforts, or management of government lands.

State land was marginally more effective than federal lands. This could reflect the history of land conservation in the state. Acadia and the White Mountains Nat. Forest, the largest federal tracts, were originally protected for their scenic (3) and timber value, while Baxter State park, the largest state conservation area, was designed to be “forever…a sanctuary for beasts and birds” (4).

Ownership Type

Leases were excluded from the comparison since leases account for only 0.07% of conservation lands in Maine. Land owned fee simple contained a greater percentage of its area that is not suitable for the protected species analyzed (Figures 5, 6). Therefore, the null hypothesis that there is no difference between the presence and absence of listed species on lands owned fee simple and under lease was rejected (p < 0.001). However, land owner fee simple contained a greater percentage of land that was suitable for 2 or more species than land held under easement. This may be a reflection of different management practices, since easements protect land from some development, but other agricultural and forestry practices may still be allowed.

There were strong similarities between the public-private and easement-fee simple comparisons. This may be explained by the fact that 80% of all private conservation land is held under easement.

Data Quality

The GAP data used as the base of this analysis shows where habitat suitable for certain species is, not where the species actually occur. The GAP data analysis is based off environmental factors such as elevation, temperature, and land cover type, which are all subject to their individual flaws which are incorporated into the GAP data too. The GAP data is also subject to flaws in the integration of the environmental factors and assumptions of the analysis. Our results cannot claim that Maine conservation lands do or do not effectively protect endangered species themselves, nonetheless, protecting habitat suitable for endangered or threatened species is important.

The species we picked for the analysis also limit the thoroughness of our results. We chose 13 vertebrate terrestrial species for which GAP data was available. Some species, such as the Piping Plover and Roseate Tern, had nesting data available but not GAP layers so they were excluded for consistency. Other species such as the Harlequin Duck and Eastern Cottontail had no data. Data was also not available for invertebrate species. Therefore, it is possible that some of the area classified as having no listed species present may in fact be suitable for some of the excluded species.

Despite the flaws of this analysis, we did show that Maine’s conservation lands are effective in protecting habitat for thirteen important species. As more data becomes available on the distribution of threatened species, we hope that future studies will expand on our results.

Works Cited

(1) “Endangered Species Program”. USFWS: Endangered Species Act of 1973. 2008. FWS. 24 April 2009. <http://www.fws.gov/Endangered/esa/content.html >

(2) Endangered Species Act of Maine. Maine Dept. of Inland Fisheries and Wildlife, 2007. Accessed: 4-24-09

(3) Baxter State Park <http://www.baxterstateparkauthority.com/>

(4) Acadia National Park <http://www.nps.gov/acad/>

Metadata

Maine Offics of GIS <http://megis.maine.gov/>

USGS National Biological Information Infrastructure <http://gapanalysis.nbii.gov/portal/server.pt>

Acknowledgments

We would like to extend our thanks to Prof. Philip Nyhus and Dr. Manuel Gimond for their advice and support. We would also like to thank the Oak Foundation for the use of the GIS facilities and David Kazyak for the background photograph.

Appendix

Map showing conservation land and habitat values in Maine