Amphibians and Reptiles in Oregon: Oregon Spotted Frog, Columbia Spotted Frog, Western Pond Turtle, and Western Painted Turtle.

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1 Appendix G Amphibians and Reptiles in Oregon: Oregon Spotted Frog, Columbia Spotted Frog, Western Pond Turtle, and Western Painted Turtle. This appendix discusses four amphibians and reptiles that likely will be listed as threatened or endangered pursuant to the Endangered Species Act: the Oregon spotted frog, the Columbia spotted frog, the Western pond turtle, and the Western painted turtle. I. The Oregon Spotted Frog 1 The Oregon spotted frog has been lost from at least 78 percent of its former range. In 1993, the USF&WS determined the Oregon spotted frog warranted ESA listing however it has remained a 2 candidate species ever since. A status review was conducted in December 2007 which has been 3 updated annually through The species is known to exist in 43 sites in the United States, 31 of which are in Oregon, and 89 percent of which are in partial public ownership. USF&WS states that due to its small populations in these sites, many of them are at risk of extirpation 4 from stochastic events. Pesticides are known to negatively affect various life stages of a wide 5 range of amphibian species, including ranid frogs[.] For this reason USF&WS notes that In 1999, Four Rivers Vector Control planned to apply pyrethroids, methoprene, and other pesticides in wetlands and other bodies of water within the range of the Oregon spotted frog. This company is funded primarily by homeowners, homeowner associations, and businesses in the Sunriver area of Oregon to control mosquitoes. Due to the concerns about the use of methoprene and the possible effects of the mosquito abatement program on the Oregon spotted frog, the company is not permitted to use the chemical on the Deschutes National Forest and is voluntarily restricting its use to a few sites. Similar proposals are possible in the future. 6 That restriction on pesticide applications was established over 12 years ago and there is no evidence that any other such restrictions have been placed on either public or private lands to provide protection for the Oregon spotted frog, a species for which ESA-listing is warranted and 7 for which the USF&WS has concluded threats to this species are imminent[.] 1 USF&WS, Species Fact Sheet, Oregon spotted frog, Rana pretiosa, (last accessed July 27, 2012). 2 3 USF&WS, U.S., Fish and Wildlife Service Species Assessment and Listing Priority Assignment Form, Common Name: Oregon spotted frog (April 2010) available at (last accessed July 27, 2012) at 38. at 29. at at 39.

2 II. The Columbia Spotted Frog Similarly, the Columbia spotted frog was determined by USF&WS to warrant threatened status under the ESA but in 1993 that listing was precluded by higher priority actions and it has 8 remained on the candidate list ever since. Of the three states in which the Columbia spotted frog lived historically, it is now found in a total of seven counties in the United States, three of which 9 are in Oregon (Lake, Harney, and Malheur). Ninety percent of the lands with known habitat are 10 federally managed by the U.S. Forest Service or Bureau of Land Management. USF&WS has noted that the Columbia spotted frog populations have continued to decline... despite the analyses pursuant to N[ational]E[nvironmental]P[olicy]A[ct] on all Federal actions potentially 11 affecting the Columbia spotted frog and analyses pursuant to NEPA on public lands. As an indication of the vulnerability of this species to extinction, Oregon has classified the Oregon spotted frog as imperiled and vulnerable to extirpation and extinction in the State. USF&WS expresses concern about the use of pesticides where they can expose the Columbia spotted frogs: Use of pesticides for control of grasshoppers (Melanoplus sp.) and crickets (Anabrus simplex), as well as use of herbicides to treat weeds and other vegetation, may be impacting some populations of Columbia spotted frogs, particularly on private property. While we have no evidence to suggest frogs have been directly affected in the past, we do know substantial amounts of carbaryl (used in insecticide applications) and atrazine (used in herbicide applications) are used in Nevada and Idaho (Idaho State Department of Agriculture 2009). Atrazine, even if used at levels below USEPA requirements, can cause changes in the sex ratio in amphibians (Hayes 2004, pp ). 12 The USF&WS is also concerned about the additive and synergistic effects of pesticides and other adverse conditions, such as the effect of UV light on increasing the toxicity of chemicals and 13 increasing the susceptibility of individual frogs to infection, disease, or predation. The agency concludes that [T]he current state of small fragmented populations of Columbia spotted frogs in the Great Basin indicates a high probability of populations disappearing[.] 14 8 USF&WS, U.S. Fish and Wildlife Service Species Assessment and Listing Priority Assignment Form, Common Name: Columbia spotted frog (Great Basin Distinct Population Segment) (April 15, 2010) available at (last accessed July 28, 2012) at 2. at 3. at 22. at 25. at 26.

3 III. The Western Pond Turtle There are two native species of turtles in Oregon, the Western pond turtle and the Western 15 painted turtle. ODFW states that [b]oth are highlighted in the Oregon Conservation Strategy 16 as species in need of help that is, they have low or declining populations. ODFW has 17 designated both native turtles Sensitive Species Critical. This designation means that both native turtles are naturally-reproducing fish and wildlife species, subspecies, or populations 18 which are facing one or more threats to their populations and/or habitats. And, as stated above, the designation critical means that both of these species are imperiled with local extirpations and at risk of needing to be listed as threatened or endangered because the 19 population of Western Pond Turtles has declined dramatically. Moreover The greatest danger facing Oregon's Western Pond Turtle population is low juvenile recruitment. The species requires accessible upland nesting habitat near their aquatic habitat. Fragmentation of properties and of land-use types renders this critical habitat requirement increasingly rare. While relatively large populations of mature turtles can be observed in their aquatic habitat, the rate of successful breeding and juvenile recruitment is largely unknown and believed to be too low to maintain population numbers at their current levels. In other words, existing populations in Oregon are likely getting older and few juveniles survive to replace their numbers. 20 The Center for Biological Diversity recently filed a petition with the Secretary of the Interior to 21 list, inter alia, the Western pond turtle as endangered under the ESA. According to the petition, only northern California and southern Oregon support large populations but even in those areas 22 their status is uncertain. Moreover In Oregon, the western pond turtle occurs widely but in low to very low densities (Holland 1993). Researchers observed the turtles in 83 of 313 sites surveyed in 15 ODFW, Turtles in Oregon, turtles.asp (last accessed July 27, 2012) ODFW, 2008 ODFW Sensitive Species List, organized by category 9, available at state.or.us/wildlife/diversity/species/docs/ssl_by_category.pdf (last accessed July 26, 2012). 18 at University of Oregon Environmental Leadership Program, Western Pond Turtles: Habitat and History in Oregon, (last accessed July 25, 2012) Center for Biological Diversity, Petition to List 53 Amphibians and Reptiles in the United States as Threatened or Endangered Species Under the Endangered Species Act, (July 11, 2012) available at Mega_herp_petition_ pdf. 22 at 90.

4 1991 (Holland 1993). In the Willamette Valley in Oregon, western pond turtles appear to have declined to a level that represents roughly one percent of historic levels (Holland 1991a). 23 As the petition comments The western pond turtle has special status under state law within its entire native range (Bury and Germano 2008). It is listed as state endangered in Washington, sensitive/critical in Oregon, and a species of special concern in California. But none of these laws confer effective protection of habitat. Some successful recovery actions have occurred in Washington and a conservation strategy drafted for California, but these initiatives are merely voluntary and must be considered inadequate (Allen et al. 2001, Ashton and Welsh Jr. 2009, vander Haegen et al. 2009). 24 DEQ s failure to ensure protection of this potentially endangered species from regulated discharges of pesticides demonstrates precisely how poorly the Western states have failed. USF&WS is concerned about the impacts of pesticides on the Western pond turtle. The agency investigated pesticide use in the Willamette Valley National Wildlife Refuge Complex where much of the land within the refuge is managed for grass production involving applications of 25 herbicides, fungicides, and fertilizers. The investigation concluded there could be effects to aquatic communities from exposure to atrazine and chlorpyrifos and that hormone values measured in biotic samples from refuge sites were within normal ranges except for western pond turtles at Finley National Wildlife Refuge, where higher testosterone values were observed in 26 females and the female hormone ratio was atypically low compared to reference turtles. The agency concluded [t[he pesticides of most serious concern originate outside the refuge, and refuge personnel have limited ability to manage pesticide application occurring off-refuge 27 lands. IV. The Western Painted Turtle As stated above, ODFW classifes the Western painted turtle as sensitive-critical. Threats to western painted turtles in Oregon are very similar to western pond turtles and are often 28 landscape-specific. Among the threats to the Western painted turtle are indirect effects of at USFWS, Assessment of Impacts to Aquatic Organisms from Pesticide Use on the Willamette Valley National Wildlife Refuge Complex, Pesticides and Aquatic Organisms (May 2007) FinleyNWR/default.asp (last accessed July 30, 2012) U.S. Department of the Interior, Conservation Assessment For The Western Painted Turtle In Oregon (Chrysemys picta bellii) Version 1.1 (September 2009) available at pdf.

5 pesticide use, primarily on private lands and designated open spaces managed by public 29 agencies, not the federal government. Turtles rely on wetlands as well as upland areas that are crucial for reproduction [and] are frequently not protected. Due in large part to the loss of once vast wetlands in the Columbia and Willamette River basins, declines in abundance of turtles in 30 the Willamette Basin and Columbia Basin must have been great. The agencies found that among the threats to Western painted turtle are contaminants: Broad-scale pesticide use to reduce mosquito larvae in wetland areas may reduce invertebrate prey. The largest wetlands are most likely to undergo pesticide use to reduce mosquito larvae and it is these wetlands that contain the largest remaining painted turtle populations in the Portland metropolitan region. In one wetland complex, larvicide was applied more than ten times to the wetlands perimeter during a single spring-summer season (E. Stewart, pers. obs.). Effects of repeated applications on non-target dipteran populations and wetland food webs are poorly understood. In addition, herbicide use for aquatic invasive plants may alter the availability of cover and basking sites especially for very small turtles. Other sources of water pollution may also affect western painted turtles. No information was found detailing with any of these potential threats at 6. at 26. at