1	The effects of the Brown Tree Snake (Boiga irregularis) on the native birds of Guam Sabrina Andrews, Tyler Bourret, Debbie Bushey and Erin Dawson
2	Guam: Geography and Climate
3	Guam: Geography and Climate
4	Natural History of the Brown Tree Snake
5	Natural History of the Brown Tree Snake
6	Theory on how the Brown tree snake arrived on Guam
7	Invasion of Guam
8	Native Forest Birds
9	Brown Tree Snake’s Impact on Native Forest Birds
10	Brown Tree Snake’s Impact on Native Forest Bird Species
11	Brown Tree Snake’s Impact (cont’d)
12	Explanations for Mass Extinctions on Guam
13	Nesting Seabirds White-tailed Tropicbird Brown noddy dankolo White tern Formerly nested on Guam Currently nest on nearby islands
14	Native Forest Birds Bridled White-eye Guam Broadbill Micronesian Kingfisher Mariana Crow Guam Rail
15	Native Forest Birds Noticeable declines began in the 1960’s U.S. Fish and Wildlife Service began systematic surveys in 1981
16	Bridled white-eye Habitat: all habitats Diet: Insectivore Reproduction: Nested year round Highly altricial young Nests: fine fibers woven into hanging baskets
17	Bridled white-eye Was once most common species Historically found island wide 1945: few left in southern Guam 1961: last recorded in Central Guam 1981: occupied 2% of original range 1983: last observation 1984: listed as endangered
18	Guam Broadbill Habitat: all habitats except southern savannah Diet: insectivore Reproduction: Little is known Cup nests woven and held together by spider webs and a mucous-like substance
19	Guam Broadbill 1950: 62% of its former range 1970’s: absent from southern and central Guam 1981: 460 remaining in N. Guam Early 1983 – restricted to 150 ha patch of mature limestone forest on Northern Guam Last seen in May 1984 1984: Listed as Endangered in August
20	Micronesian Kingfisher Habitat: wide variety of forested habitats Diet: animal matter Reproduction: Cavity nester requiring old rotting trees, broken branches, soft wood Territorial 1-2 clutches per year 2 eggs in each clutch
21	Micronesian Kingfisher 1970’s: Last reported in Southern Guam 1981: 3023 birds estimated in Northern Guam 1984-5: Fewer than 50 birds Collected and placed in captive breeding program 1984: Listed as endangered
22	Mariana Crow Habitat: prefers mature native forest Diet: omnivore Reproduction: Territories 2-3 acres Nests July – March Clutch size 2-4 eggs, 1-2 fledge Juvenile requires 3 years to enter breeding cohort
23	Mariana Crow Considered common during the 1960’s 1981: 357 crows estimated Most recent studies indicate only 20 remaining crows Not currently reproducing successfully 1984: Listed as endangered
24	Guam Rail Habitat: scrubby second growth or mixed forest Diet: omnivorous, prefers animal food over plant matter Reproduction: Monogamous Ground nester 2-4 eggs in shallow nest Precocial young, parents feed for 7-10 days
25	Guam Rail Prior to 1970’s: widely distributed in all habitats except wetlands mid 1970’s: disappeared from southern Guam mid-1980’s: all collected and placed in captive breeding program 1984: Listed as endangered
26	Pattern of Bird Disappearance The pattern seems to be that the birds maintain good populations, and then suddenly disappear within a year or so, along the extinction front. 1950s Some suggestions of a reduction in the numbers of Forest Birds in the mid-south of the island. 1960s Extinction of Forest Birds in the south and center of the island. 1970s Extinction of Forest Birds in much of the north. 1980s Extinction of Forest Birds in the remainder of the north complete by 1982.
27	Conservation Efforts Breeding Programs established in zoos and neighboring island Trapping and barriers used to create “snake free” areas Evaluating management techniques The Guam Rail as a model species
28	Breeding Efforts Breeding program began with 21 founders Effort to conserve the genetic diversity of the species Male rails are known to violently attack females Artificial insemination technology being explored
29	Breeding Efforts Extremely prolific with up to 10 clutches per year and 1-4 eggs in a clutch Will destroy a clutch if they are disturbed Captive bred birds are being released onto nearby island of Rota to hopefully start a wild breeding population
30	Results of Captive Breeding 800 Guam Rails produced since 1984 267 captive bred birds released onto Rota Five confirmed as breeding
31	Area 50 24 ha of limestone forest designated for reintroduction Considered potential area for Guam Rail reintroduction Trapping and barrier protection used to make the area relatively “snake free”
32	Results of Trapping Interior and perimeter traps used to reduce populations Wire mesh put around fence to act as barrier 430 snakes captured Later trapping produced only 30 snakes in same timeframe
33	Reintroduction of Rail Only rails that are genetically well represented in captive populations considered Trapping of snakes in area maintained Rail monitoring by visual observations and radio tracking
34	Area 50 Results By November 1998 16 rails were released 5 pairs established 4 confirmed as breeding By October 1999 9 rails made 16 nesting attempts 46 eggs were produced All but 6 eggs hatched
35	Problems of Area 50 Small snakes can evade traps Assumes snakes are nomadic Other predators still can threaten rail Barrier is imperfect Most rail deaths caused by scientific equipment
36	Radio Monitoring of Guam Rail
37	Other Conservation Efforts Marianas Archipelago Rescue and Survey (MARS) project is working to conserve the Mariana Crow (Corvus kubaryi) The Micronesian kingfisher (Halcyon cinnamomina cinnamomina) is part of a species survival plan in AZA institutions Don Nichols and the introduction of the paramyxovirus
38	Governmental Involvement
39	History of Invasive Species Legislation Prohibited “the import, export, transportation, sale, receipt, acquisition, or purchase of fish, wildlife, or plants taken, possessed, transported, or sold in violation of any Federal, State, tribal, or foreign law.” First piece of legislation aimed at stopping import of non-native species.
40	Endangered Species Act of 1973 Not directly involved in invasive species. Recognized the need for Species Survival Plans and started many conservation efforts. Every federal agency has a duty to protect an endangered species.
41	Federal Noxious Weed Act of 1975 Aimed at stopping the spread of invasive plants. Showed government awareness of the dangers of invasive species. Prohibited transport of plants identified as noxious weeds.
42	Nonindigenous Aquatic Nuisance Prevention and Control Act of 1990 Specifically addressed Brown Tree Snake problem. Involved more government agencies in prevention and control of invasive species. First legislation with teeth. Later amended as Invasive Species Act of 1996. Current legislation used to fight BTS.
43	Environmental Education Act of 1990 Formed new Environmental Protection Agency office in charge of environmental education at the federal level. Promotes education about environmental programs and efforts, and keeping citizens informed of their own environmental impacts.
44	Animal Damage Control Act of 1991 Gives the Secretary of Agriculture authority to investigate and control harmful predatory animals. Gives special focus to Brown Tree Snake, particularly in preventing BTS introduction to Hawaii
45	Alien Species Prevention Enforcement Act of 1992 Focused narrowly on keeping the Brown Tree Snake from being introduced to Hawaii. Mandates 4 federal agencies - the Department of Agriculture, the Department of Interior, the Postal Service, and the State of Hawaii to work together to stop the spread of the BTS.
46	Government Agencies Involved US Geological Survey Department of Fish And Wildlife Department of Defense Department of Interior Department of Commerce Department of Agriculture US Postal Service Environmental Protection Agency Commonwealth of the Northern Mariana Islands Territory of Guam State of Hawaii …and more, as well as NGO’s.
47	Government Inadequacies “The current Federal framework is a largely uncoordinated patchwork of laws, regulations, policies, and programs. Some focus on narrowly drawn problems.... In general, present Federal efforts only partially match the problems at hand.” Most invasive species legislation focuses on species after they have become a problem, not on prevention.
48	Funding Funding is allocated from the budgets of the various agencies involved. According to the The Brown Tree Snake Control Committee of the Aquatic Nuisance Species Task Force, funding needed for this problem is approximately 2.5 million dollars a year for the foreseeable future. This cost does not include other negative economic impacts of the BTS, including power loss, medical costs, loss of agriculture, etc. President Bush recently cut funding for invasive species control problems.
49	What Can You Do? Call your congressperson and tell them how you feel on the issue. Volunteer at one of the agencies involved. Tell your friends.
50	For More Information… Brown Tree Snake Info http://www.invasivespecies.gov/profiles/bts.shtml http://anstaskforce.gov/BTS%20Control%20Plan.htm http://www.mesc.usgs.gov/resources/education/bts/default.htm Conservation Effort for Guam Rail http://members.tripod.com/allan_searle/Area50BTSGuam.html http://fwie.fw.vt.edu/WWW/esis/lists/e101035.htm http://cnie.org/NLE/CRSreports/Biodiversity/biodv-21.cfm
51	"Other birds of Guam" Other birds of Guam http://ibs.uel.ac.uk/ibs/envmath/cal/env203/guam http://www. mesc.usgs.gov/resources/education/bts/impacts/birds http://pacificislands.fws.gov/webmap.html http://www.orecity.k12.or.us/ochs/departments/science/species/kingfisher.html Bridled white-eye http://fwie.fw.vt.edu/WWW/esis/lists/e101031.htm Mariana Crow http://fwie.fw.vt.edu/WWW/esis/lists/e101032.htm Guam Broadbill http://fwie.fw.vt.edu/WWW/esis/lists/e101033.htm Micronesian Kingfisher http://fwie.fw.vt.edu/WWW/esis/lists/e101034.htm http://www.orecity.k12.or.us/ochs/departments/science/species/kingfisher.html
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