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Welcome to BEACHMOUSE.COM |
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Written by Web Master
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Saturday, 12 June 2004 |
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The Perdido Key Beach Mouse Today
Dune plants are the primary source of food for the endangered Perdido Key Beach Mouse. The small white and gray mouse, weighing only 13-16 grams, blends in well with the white quartz sand of northern Gulf coast beaches. While the Perdido Key Beach Mouse feeds primarily on the seeds of sea oats and bluestem, it will occasionally eat insects. The Perdido Key beach mouse is a nocturnal animal, spending most daylight hours in their burrows. Unlike many species, Beach Mice are monogamous, with mated pairs tending to remain together as long as both live. A typical beach mouse pair averages 3-4 offspring per litter and has roughly 3 litters per year. In contrast to its inland relatives, the Perdido Key Beach Mouse steers clear of people, buildings and trash, instead  preferring to meander among the dunes near its burrow. Mouse burrows are usually located in the dunes at the base of a shrub, clump of grass or near some vegetated cover. The burrow itself consists of an entrance tube, a nest cavity, and an escape tube which is closed off but near the surface of the sand. If an intruder, such as a snake or crab, enters a beach mouse burrow, mice make a hasty retreat out the escape tube. The Perdido Key beach mouse was listed as an endangered species in 1985. Loss of habitat to development is considered to be the main factor which led to the decline of the species. Hurricanes have also taken their toll on the endangered mouse.The beach mouse population at Perdido Key was nearly wiped out in the mid-1990's when hurricanes Erin and Opal ravaged Perdido Key’s beaches. Numbering less than 40 after the storms, the mice have regenerated quite well, with current population estimates near 500. While populations appear to be growing, the Perdido Key Beach Mouse will probably never make it off the endangered species list because of continued habitat loss and degradation. The Perdido Key Beach Mouse
Dune plants are the primary source of food for the endangered Perdido Key Beach Mouse. The small white and gray mouse, weighing only 13-16 grams, blends in well with the white quartz sand of northern Gulf coast beaches. While the Perdido Key Beach Mouse feeds primarily on the seeds of sea oats and bluestem, it will occasionally eat
insects.
The Perdido Key beach mouse is a nocturnal animal, spending most daylight hours in their burrows. Unlike many species, Beach Mice are monogamous, with mated pairs tending to remain together as long as both live. A typical beach mouse pair averages 3-4 offspring per litter and has roughly 3 litters per year.
In contrast to its inland relatives, the Perdido Key Beach Mouse steers clear of people, buildings and trash, instead preferring to meander among the dunes near its burrow. Mouse burrows are usually located in the dunes at the base of a shrub, clump of grass or near some vegetated cover. The burrow itself consists of an entrance tube, a nest cavity, and an escape tube which is closed off but near the surface of the sand. If an intruder, such as a snake or crab, enters a beach mouse burrow, mice make a hasty retreat out the escape tube.
The Perdido Key beach mouse was listed as an endangered species in 1985. Loss of habitat to development is considered to be the main factor which led to the decline of the species. Hurricanes have also taken their toll on the endangered mouse.The beach mouse population at Perdido Key was nearly wiped out in the mid-1990's when hurricanes Erin and Opal ravaged Perdido Key’s beaches. Numbering less than 40 after the storms, the mice have regenerated quite well, with current population estimates near 500. While populations appear to be growing, the Perdido Key Beach Mouse will probably never make it off the endangered species list because of continued habitat loss and degradation.
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Last Updated ( Wednesday, 14 February 2007 )
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Peromyscus Polionotus Trissyllepsis |
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Written by Publisher
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Monday, 09 August 2004 |
PERDIDO KEY BEACH MOUSE
Peromyscus polionotus trissyllepsis
FAMILY: Muridae
STATUS: Endangered, Federal Register, June 6, 1985
DESCRIPTION: The Perdido Key beach mouse has a small body, haired tail, relatively large ears, and protuberant eyes. Its head and body length is 2.7 to 3.3 inches; the tail length is 1.7 to 2.5 inches. The upper parts are colored grayish fawn to wood brown with a very pale yellow hue and an indistinct middorsal stripe. The white of the underparts reaches to the lower border of the eyes and ears, and the tail is white to pale grayish brown with no dorsal stripe. This species is a nocturnal herbivore. Beach mice feed primarily on the seeds of sea oats (Panicum repens) and beach grass (Panicum amarums). When these seeds are scarce, especially in the late winter or early spring, beach mice may consume invertebrates (Ehrhart in Layne, 1978) or fruiting bodies of sea rocket (Cakile) sp. (U.S. Fish and Wildlife Service, 1987).
REPRODUCTION AND DEVELOPMENT: Based on studies of other subspecies of P. polionotus, it can be inferred that reproduction may occur throughout the year, but peak during November, December, and January. Beach mice litters may range from two to seven, and the young may reach sexual maturity by 6 weeks of age. Results of a laboratory study (Blair 1968) show that female beach mice are capable of producing litters every 26 days, and they may produce 8O or more young in their lifetimes. Studies of other closely-related beach mouse species indicate that beach mouse life spans may be short, ranging from less than 5 months in the wild to over 3 years (Blair 1948).
RANGE AND POPULATION LEVEL: The Perdido Key beach mouse currently survives on the western part of Perdido Key including the Gulf State Park, Baldwin County, Alabama and on the eastern part of the key at the Gulf Islands National Seashore, Escambia County, Florida. The mouse has been reestablished on the Gulf Island National Seashore. The species is presumed to have once inhabited the entire key. The Perdido Key State Preserve is located in the central part of Perdido Key. Beach mouse habitat exists in the Preserve, although it is less than optimum in terms of average dune height.
Trapping at Gulf State Park in 1990 yielded approximately 48 mice in designated critical habitat. The estimated population varied between 48 and 167 animals between November 1988 and May 1991 (Holler, unpublished data). Three trapping surveys at Gulf Islands National Seashore in 1991 resulted in a population estimate range of 85 to 118 mice (Holler and Moyers, 1991). Trapping at Gulf Islands National Seashore is an ongoing project initiated in 1989 to monitor the Perdido Key beach mouse population during and after a major beach renourishment program. A captive breeding colony has been established and housed at Auburn University, Alabama to provide beach mice where reintroduction is necessary to restore the wild populations, due to the potential of loss due to a catastrophic event (Holler, pers. comm.).
HABITAT: The habitat is restricted to the mature coastal barrier sand dunes along the Gulf. The depth of the habitat extending inland may vary depending on the configuration of the sand dune system and the vegetation present. There are commonly several rows of dunes paralleling the shoreline and within these rows there are generally three types of microhabitat.
The frontal dunes are sparsely vegetated with widely scattered coarse grasses including sea oats (Uniola paniculata), bunch grass (Andropogon maritimus), and beach grass (Panicum amarum and P. repens), and with seaside rosemary (Ceratiola ericoides), beach morning glory (Ipomoea stolonifera), and railroad vine (I. pes-caprae). Frontal dune grasses also appear as a lesser component on the higher rear dunes.
The interdunal areas contain sedges (Cyperus sp.), rushes (Juncus scirpoides), and salt-grass (Distichlis spicata).
The dunes farther inland from the Gulf support growths of slash pine (Pinus elliotti), sand pine (P. clausa), scrubby shrubs and oaks, including yaupon (Ilex vomitoria), marsh elder (Iva sp.), scrub oak (Quercus myrtifolia), and sand-live oak (Q. virginiana var. maritima).
The beach mice dig burrows mainly on the lee side of the primary dunes and in other secondary and interior dunes where the vegetation provides suitable cover. The mice may also use ghost crab (Ocypoda quadratus) burrows.
CRITICAL HABITAT: Alabama. An area of land, water, and airspace in Baldwin County with the following components (Tallahassee Meridian): that portion of the Perdido Key unit of the Gulf State Park south of State Road 182 in T9S R33W Sec. 2-3, Florida. Areas of land, water, and airspace in Escambia County with the following components (Tallahassee Meridian): (1) that portion of the Perdido Key State Preserve south of State Road 292 in T3S R31W Sec. 25-26 and Sec. 28-34, and in T3S R32W E 1/2 Sec. 36, and W 1/2 Sec. 36 south of the entrance road, parking lot, and Johnson Beach recreational facilities at the Gulf Islands National Seashore.
Within these areas the major constituent elements that are known to require special management considerations and protection are dunes and interdunal areas, and associated grasses and shrubs that provide food and cover.
REASONS FOR CURRENT STATUS: Tropical storms and loss of habitat are considered to be primary factors in the mouse's decline. It is estimated that approximately 34 percent of the island has been developed and is no longer suitable habitat. Commercial and residential development, especially if the latter is high density multiple housing, isolates small areas of beach mouse habitat thereby fragmenting populations and upsetting gene flow. Such barriers also prevent recolonization of an area should a population segment be extirpated.
Tropical storms periodically devastate Gulf Coast sand dune communities, dramatically altering or destroying habitat, and either drowning beach mice or forcing them to concentrate on high scrub dunes where they are exposed to predators. The Gulf State Park area was severely flooded by Hurricane Frederick on September 13, 1979. Washovers completely destroyed mouse habitat on all dunes less than 11.5 feet high, leaving only the dune ridges in excess of this height as habitat. At the eastern end of the Key in Gulf Islands National Seashore, 80 percent of the area was overwashed during the hurricane, but has since recovered.
Other threats include feral house cats, which may prey on beach mice, and house mice (Mus musculus) which may possibly compete with beach mice for food and cover.
MANAGEMENT AND PROTECTION EFFORTS: The most effective conservation measures would be the preservation of the remaining privately-owned mature sand dune systems, and the protection and enhancement of the publicly-owned sand dune systems at the Gulf State Park, Perdido Key State Preserve, and the Gulf Islands National Seashore. On the publicly-owned lands, strict exclusion of off-read vehicles from the sand dunes would allow ecological succession to reestablish good beach mouse habitat. Strict control of pedestrian access across the dunes, by limiting pedestrians to elevated boardwalks, would also serve to protect the fragile dune vegetation. The planting of native dune vegetation would enhance ecological succession in severely eroded areas. Healthy mature sand dunes have a better chance of withstanding the impacts of tropical storms, thus protecting beach mouse habitat, than do eroded dunes.
Both Alabama and Florida have statutes which generally protect sea oats against picking, but these laws provide no protection against loss from land conversion activities.
Associated with residential and commercial development are feral house cats, which may prey upon beach mice, and house mice which may compete with beach mice for food. The control of feral house cats and house mice would be desirable and could be achieved through an aggressive public education program. The installation of animal-proof refuse containers and efficient refuse disposal systems might attract fewer potential mouse predators.
Perdido Key is located between the Perdido Pass Entrance Channel and the Pensacola Bay Channel. Both of these channels are maintained by the U.S. Army Corps of Engineers. With the careful dredging of accreted sands and placement of spoil, beach mouse habitat should not be adversely affected by the routine maintenance operations.
Since the Gulf coast is regularly subjected to tropical storms, a prudent conservation measure is to insure that populations of beach mice become established on the public lands from which the mice have been extirpated in recent years, specifically the Perdido Key State Preserve and the Gulf Islands National Seashore. Captive breeding of beach mice with subsequent release of offspring in the wild is a possible means of reintroduction. Another measure might be the translocation of some beach mice from the Gulf State Park to other suitable sites on Perdido Key.
REFERENCES:
Bowen, W.W. 1968. Variation and evolution of Gulf Coast populations of beach mice, Peromyscus polionotus. Bull. Alabama Mus. Nat. Hist., no. 2, pp. 88-92.
Blair, W.F. 1948. Population Density, Life Span, and Mortality Rates of Small Mammals in the Blue-grass Meadow and Blue-grass Field Associations of Southern Michigan. Amer. Midl. Nat., 4O:395-419
Ehrhart, L.M. 1978. Choctawhatchee Beach Mouse. In Layne, J.N. (ed.) Rare and Endangered Biota of Florida Volume 1, Mammals. Univ. Presses of Florida, Gainesville, pp. 18-19.
Holler, N. R., D.W. Mason, R.M. Dawson, T. Simmons, and M.C. Wooten. 1989. Reestablishment of the Perdido Key Beach Mouse (Peromyscus polionotus trissyllepsis) on Gulf Islands National Seashore. Conserv. Biol. 3:397-404.
Holliman, D.C. 1983. Status and habitat of Alabama Gulf Coast beach mice (Peromyscus polionotus ammobates and P. p. trissyllepsis). Northeast Gulf Science 6(2):121-129.
Humphrey, S.r., and D.B. Babour. 1981. Status and Habitat of Three Subspecies of Peromyscus polionotus in Florida. J. Mamm. 62:840-844.
Linzey, D.W. 1978. Perdido Bay Beach Mouse. In Layne, J.N. (ed.). Rare and Endangered Biota of Florida. Volume 1, Mammals. University Presses of Florida, Gainesville. pp. 19-20.
Meyers, J.M. 1983. Status, Microhabitat, and Management Recommendations for Peromyscus polionotus on Gulf Coast Beaches. Rept. to U.S. Fish and Wildl. Serv., Atlanta. 29 pp.
U.S. Fish and Wildlife Service. 1985. Endangered and Threatened Wildlife and Plants; Determination of Endangered Status and Critical Habitat for Three Beach Mice. Federal Register 5O(1O9): 23872-23889.
**U.S. Fish and Wildlife Service. 1987. Recovery Plan For The Alabama Beach Mouse (Peromyscus polionotus ammobates), Perdido Key Beach Mouse (P. p. trissyllepsis), and Choctawhatchee Beach Mouse (P. p.. allophrys). U.S. Fish and Wildlife Service, Atlanta, Georgia. 45 pp.
For more information please contact:
U.S. Fish and Wildlife Service
6578 Dogwood View Parkway
Suite A
Jackson, Mississippi 39213
Telephone: 6O1/965-49OO
U.S. Fish and Wildlife Service
31OO University Boulevard, South
Suite 12O
Jacksonville, Florida 32216
Telephone: 9O4/791-258O
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Last Updated ( Thursday, 08 February 2007 )
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Anastasia Island Beach Mouse |
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Written by Publisher
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Monday, 09 August 2004 |
U.S. FISH AND WILDLIFE SERVICE
DIVISION OF ENDANGERED SPECIES
SPECIES ACCOUNTS
Source: Endangered and Threatened Species of the Southeastern United States (The Red Book) FWS Region 4 -- As of 8/91 SOUTHEASTERN BEACH MOUSE Peromyscus polionotus niveiventris ANASTASIA ISLAND BEACH MOUSE Peromyscus polionotus phasma FAMILY: Cricetidae STATUS: Anastasia Island beach mouse is Endangered. Southeastern beach mouse is Threatened. (Federal Register, May 12, 1989) DESCRIPTION: The Anastasia Island beach mouse and the Southeastern beach mouse are two of six existing coastal subspecies of the oldfield mouse (Peromyscus polionotus). The oldfield mouse is a wide-ranging species in the Southeast. One of the largest species of beach mice (averaging 138.5 millimeters in length and 53 millimeters in tail length), the Anastasia Island beach mouse is much paler than most inland races of the oldfield mouse. This beach mouse has a light buff-colored back, pure white underparts, and indistinct, white markings on its nose and face (Howell, unpublished. ms., circa 194O). The Southeastern beach mouse is the largest beach mouse; it averages 139 millimeters in total length and 52 millimeters in tail length. Although it is darker and more buffy than the Anastasia Island beach mouse, it is still lighter than most inland subspecies of the oldfield mouse. RANGE AND POPULATION LEVEL: The historic range of the threatened Southeastern beach mouse was north Florida's Mosquito (Ponce) Inlet in Volusia County to south Florida's Hollywood Beach in Broward County. Now, the Southeastern beach mouse has apparently been eliminated from the southern section of its habitat at Jupiter Island, Palm Beach, Lake Worth, Hillsboro Inlet, and Hollywood Beach. Beach mice also may be gone from the East Peninsula. Humphrey (1987) sighted only a few small, fragmented populations between Sebastian Inlet to Hutchinson Island. The healthiest populations appear to occur on public lands: Cape Canaveral National Seashore; Merritt Island National Wildlife Refuge; Cape Kennedy Air Force Station; the southern half of Sebestian Inlet State Recreation Area, and Pepper Park. Apparently once ranging from north Florida's St. John's River to south Florida's Anastasia Island, the endangered Anastasia Island beach mouse may remain only on Anastasia Island. Some suitable habitat still exists in the north between Ponte Vedra Beach and South Ponte Vedra Beach in St. John's County (Guana River Wildlife Management Area), but no mice have been found there. Much of Anastasia Island has undergone residential development, and viable mice populations may be restricted to the State Recreation Area and Fort Matanzas National Monument. HABITAT: Both species inhabit sand dunes which are vegetated by sea oats and dune panic grass. The scrub adjoining these dunes is populated by oaks and sand pine or palmetto. A study conducted on Merrit Island indicated that the Southeastern beach mice may prefer open sand habitat with clumps of palmetto and sea grapes, or dense scrub habitat dominated by palmetto, sea grape, and wax myrtle; over seaward habitat with sea oats (Extine and Stout 1987). Little specific information exists about these species' burrowing habits, although they are presumed to be similar to those of beach mice on the Gulf Coast. Sometimes beach mice use the former burrows of ghost crabs, but usually they dig their own. Burrow entrances are generally found on the sloping side of a dune at the base of a clump of grass (Ehrhart in Layne 1978). The burrows are used for nesting and food storage as well as a refuge. BIOLOGICAL INFORMATION: Breeding activities may be similar to those of beach mice on the Gulf Coast. The breeding season for beach mice appears to start in November and end in early January (Blair 1951). The female, which may reach reproductive maturity at 6 weeks of age, produces two to seven beach mice per litter. A female beach mouse can usually produce liters at 2O-day intervals, but mortality is high. Most of the progeny will not survive over 4 months. Predictably, beach mice feed on sea oats and beach grasses. The sea oats must be blown to the ground for the mice to eat. During the spring and early summer when seeds are scarce, beach mice may eat invertebrates (Ehrhart in Layne 1978). REASONS FOR CURRENT STATUS: Both of these species are primarily threatened by beach and residential development which has eliminated suitable habitat. Predators such as raccoons, skunks, snakes, great-blue herons, dogs, and cats pursue the species (Myers 1983). Competitors, such as house mice, are also threats. The control of free-ranging housecats has been identified as important to the species' survival. MANAGEMENT AND PROTECTION: Most of the remaining habitat for both species is on public land, and management efforts have centered around the control of house mice. Facilities for the public have been located inland of the dune grassland. This includes campgrounds, park concessions, refuse dumpsters, or anywhere else where house mice could survive. The Florida Game and Fresh Water Fish Commission is conducting a study of populations, habitat requirements, and conservation needs for the Anastasia Island beach mouse (Mike Bentzien, U.S. Fish and Wildlife Service, Personal Communication). REFERENCES: Blair, W.F. 1951. Population Structure, Social behavior and Environmental Relations in a Natural Population of the Beach Mouse (Peromyscus polionotus leucocephalus). Contrib. Lab. Vert. Biol., Univ. Michigan 48:1-47. Bowen, W.W. 1968. Variation and Evolution of Gulf Coast Populations of Beach Mice (Peromyscus polionotus), Bull. Florida State Mus. Biol. Sci. 12:1-91 Department of the Interior. Fish and Wildlife Service. Endangered and Threatened Wildlife and Plants: Endangered Status for the Anastasia Island Beach Mouse and Threatened Status for the Southeastern Beach Mouse. Federal Register. Vol. 54. No. 91. May 12, 1989. pp. 2O598 to 2O6O2. Extine, D.D. and L.J. Stout. 1987. Dispersion and Habitat Occupancy of the Beach Mouse (Peromyscus polionotus niveiventris). Mammal 68:297-3O4 Hall, E.R. 1981. The Mammals of North America. John Wiley and Sons, New York. 1175 pp. Humphrey, S.R. and D.B. Barbour. 1981. Status and Habitat of Three Subspecies of Peromyscus polionotus in Florida. J. Mammal. 62:84O-844. Humphrey, S.R. 1987. Status Survey of Seven Florida mammals. Florida Cooperative Fish and Wildlife Research Unit Tech. Report. No. 25. Gainesville, Florida. 39 pp. Layne, J.N. (ed.). 1978. Rare and Endangered Biota of Florida, Volume 1, Mammals. Univ. Presses of Florida, Gainesville, pp. 18-19. Myers, J.M. 1983. Status, Microhabitat, and Management Recommendations for Peromyscus polionotus on Gulf Coast beaches. Rept. to U.S. Fish and Wildlife Service. Atlanta, Georgia. 29 pp. Osgood, W.H. 19O9. Revision of the Mice of the American genus Peromyscus. North American Fauna 28:65 pp. For more information please contact: U.S. Fish and Wildlife Service
31OO University Boulevard South Suite 12O
Jacksonville, Florida 32216 Telephone: 9O4/791-258O |
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Last Updated ( Thursday, 08 February 2007 )
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