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Notice of Intent to Prepare an Environmental Impact Statement Related to Experimental Removal of Barred Owls for the Conservation Benefit of Threatened Northern Spotted Owls

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Fish and Wildlife Service, Interior.


Notice of intent to prepare an environmental impact statement.


Under the National Environmental Policy Act of 1969 (NEPA), this notice advises the public that we, the U.S. Fish and Wildlife Service (USFWS), intend to gather information necessary to prepare an environmental impact statement (EIS) for barred owl (Strix varia) removal experiments designed to determine if the species' presence is affecting northern spotted owl (Strix occidentalis caurina) population stability and growth, and to test the feasibility of removing barred owls from specific locations. We furnish this notice to advise other agencies and the public of our intentions, and to obtain suggestions and information on the scope of issues to include in the EIS.


To ensure consideration, please send your written comments by January 11, 2010. Interested parties may contact us for more information at the addresses and phone numbers listed in ADDRESSES.


You may submit information by one of the following methods:

1. You may mail written comments and information to Paul Henson, Field Supervisor, U.S. Fish and Wildlife Service, Oregon Fish and Wildlife Office, 2600 SE. 98th Ave., Ste. 100, Portland, OR 97266.

2. You may hand-deliver written comments to the above address.

3. You may send comments by electronic mail (e-mail) to Please see the “Request for Information” section below for file format and other information about electronic filing.

4. You may fax your comments to 503-231-6195.

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Robin Bown, U.S. Fish and Wildlife Service, Oregon Fish and Wildlife Office, 2600 SE. 98th Ave., Ste. 100, Portland, OR 97266; telephone, 503-231-6179; facsimile, 503-231-6195.

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We listed the northern spotted owl as threatened in June 1990 under the Endangered Species Act of 1973, as amended (ESA; 16 U.S.C. 1531 et seq.), based primarily on the loss and degradation of suitable habitat by human activity and natural events (55 FR 26114). Conservation efforts for the northern spotted owl since the species' listing have focused mainly on securing forest habitat with characteristics essential for its survival and conservation. The 1989 Status Review Supplement for the northern spotted owl indicated that the long-term impact of the expansion of the barred owl into the range of the spotted owl was unknown, but of concern (USFWS 1989, p. 3.15). This assessment was mirrored in the listing rule for the northern spotted owl, which noted that the long-term impact of barred owls on the spotted owl was unknown but of considerable concern (55 FR 26114, p. 26190). However, the best available information now suggests that competition from barred owls poses a significant threat to the northern spotted owl, because barred owls have continued to expand and saturate their range throughout the listed range of the northern spotted owl. Therefore, securing habitat alone may not result in the recovery of the northern spotted owl.

In the past century barred owls have expanded their range westward, reaching the range of the northern spotted owl in British Columbia by about 1959. Barred owl populations have continued to expand southward within the range of the northern spotted owl, and were first documented in that portion of Washington in 1973, Oregon in 1972, and California in 1976 (Livezey et al. 2007, p. 49; Sharp 1989, p. 179). The population of barred owls behind the expansion front continues to increase, and they now outnumber spotted owls in many of the northern portions of the northern spotted owl's range (Pearson and Livezey 2003, p. 272).

Competition and predation from barred owls may cause direct and indirect negative effects to the northern spotted owl. This threat could result in extirpation of the northern spotted owl from a substantial portion of its historical range and severely reduce the likelihood of its recovery, even if other known negative effects are eliminated.

Potential direct negative effects include declines in site occupancy by northern spotted owls resulting from their exclusion from high-quality habitat by barred owls. This exclusion drives Start Printed Page 65547northern spotted owls from forests that contain characteristics necessary for breeding, feeding, and sheltering, reducing the potential for northern spotted owl survival and reproduction and contributing to a declining population. In addition, barred owls may physically attack spotted owls during interactions between individuals (Gutierrez et al. 2007, p. 187). These effects may help explain declines in northern spotted owl territory occupancy associated with barred owls in Oregon, where they are recent invaders, and reduced northern spotted owl survivorship and sharper population declines in Washington, where barred owls have been present the longest and in the greatest densities (Anthony et al. 2006, pp. 21, 30, 32).

Indirect effects may also occur if the presence of barred owls suppresses the response of northern spotted owls to surveys conducted prior to forest management activities. In some situations, the presence of northern spotted owls detected during pre-project surveys results in changes to management activities, thus protecting habitat and northern spotted owls. Current research shows a suppression effect in northern spotted owl responses to surveys when barred owls are present, which could cause many northern spotted owls to go undetected (Crozier et al. 2006, p. 767). Thus, occupied habitat could end up being modified or destroyed, thereby reducing site occupancy, survival, and reproduction of northern spotted owls.

We are proposing to conduct experiments to determine if the removal of barred owls would increase the site occupancy, survival, reproduction, and population trends of northern spotted owls. Support for these experiments has been expressed in the scientific community, as indicated in the following examples. Gutierrez et al. (2007, p. 181) stated “only through carefully designed experiments involving removal of barred owls will we be able to determine if recent declines in spotted owl populations are caused by barred owls or by other factors.” Gutierrez et al. (2007, p. 191) goes on to state “[c]orrectly executed removal experiments should provide an unambiguous result regarding the effect of barred owls on spotted owl population declines.” The Wildlife Society sent a letter to the Director of the USFWS stating “experiments to remove and control barred owls * * * [are] appropriate” (The Wildlife Society 2008, p. 11). Buchanan et al. (2007, p. 683) state “[d]espite the potential for confounding effects, appropriately designed removal experiments should provide the strongest inference regarding the magnitude of the Barred Owl's effect on Spotted Owls.”

The methods for, and effects of, removing barred owls from northern spotted owl habitat are not fully understood. Two publications provide discussion and analysis of various methods of barred owl control: “A synopsis of suggested approaches to address potential competitive interaction between Barred Owls (Strix varia) and Spotted Owls (Strix occidentalis)” (Buchanan et al. 2007) and “Considering control of invasive barred owls to benefit California spotted owls: possible justification and draft methods,” in Managing Vertebrate Invasive Species: Proceedings of an International Symposium (Livezey et al. 2007). The USFWS will consider the information in these documents in developing any experimental design for barred owl removal.

The experimental design for removal studies would likely consider multiple experimental sites and a paired sample design, including treatment areas where barred owls are removed and appropriate control areas where they are not. Experimental sites would likely include 1 or more of the 14 demographic study areas where existing, long-term studies of northern spotted owl population dynamics have been under way for nearly two decades (Anthony et al. 2006). This would allow us to compare northern spotted owl population data before and after experimental barred owl removal. Paired samples (i.e., treatment and control areas) allow us to evaluate and address natural variation that might otherwise obscure the results potentially requiring longer or more extensive experiments to detect meaningful changes. Barred owl removal could involve lethal methods (killing), nonlethal methods (capture and relocation), or a combination of these, all of which will be considered in the NEPA process. Implementation of the experiments would likely occur over a period of approximately 3 to 10 years, beginning in 2010 or later and would require a permit under the Migratory Bird Treaty Act (16 U.S.C. 704).

Environmental Review of this Proposal

Prior to conducting this research, we will review the likely environmental effects and document the information in an EIS. A first step in preparing an EIS is to clearly identify the purpose(s) and need(s) for the proposed action. Our proposed research has the following three purposes:

(1) To contribute to fulfilling the intent of the ESA so ultimately, the protections afforded by the ESA are no longer necessary and the northern spotted owl may be removed from the list of threatened and endangered species;

(2) To obtain information regarding the effects of barred owls on northern spotted owl vital rates of occupancy, survival, reproduction, and population trend through experimental removal; and

(3) To determine the feasibility of removal of barred owls.

The need for the proposed research is to:

(1) Evaluate the response of northern spotted owl occupancy, survival, reproduction, and population trend to barred owl removal;

(2) Determine if barred owls can be effectively removed from an area and how much follow-up effort is required to maintain low population levels of barred owls; and

(3) Determine the cost of removal in different types of landscapes.

We will analyze a full range of reasonable alternatives meeting the purpose and need and the associated impacts of each. Potential alternatives considered to date for analysis in the EIS include, but are not limited to: (1) No experimental removal of barred owls, the No Action Alternative; (2) lethal experimental removal of barred owls; and (3) nonlethal experimental removal of barred owls, through relocation or captivity.

The environmental review of this project will be conducted in accordance with the requirements of NEPA, the National Environmental Policy Act Regulations (40 CFR 1500-1508), other appropriate Federal laws and regulations, and policies and procedures of the USFWS for compliance with those laws and regulations.

Request for Information

Comments and suggestions are invited from all interested parties to ensure consideration of a full range of alternatives related to the purpose and need and identification of all significant issues. We request that comments be as specific as possible in regard to the above-mentioned purposes and needs. We also request that comments include information, issues, and concerns regarding:

(1) The direct, indirect, and cumulative effects that implementation of one of the listed alternatives could have on endangered and threatened species and their habitats;

(2) Other possible alternatives and their associated effects;

(3) Potential adaptive management or monitoring provisions;Start Printed Page 65548

(4) Baseline environmental conditions within the range of the northern spotted owl;

(5) Other plans or projects that might be relevant to this project;

(6) Measures that would minimize and mitigate potentially adverse effects of the proposed project;

(7) Considerations for the ethical and humane treatment of barred owls removed during the experiments; and

(8) Any other information pertinent to evaluating the effects of this project on the human environment.

The environmental review will analyze and document the effects the considered alternatives would have on barred owls and northern spotted owls, as well as other components of the human environment, including but not limited to cultural resources, social resources (including public safety), economic resources, and environmental justice.

If you wish to comment, you may submit your comments and materials concerning this proposal by any one of several methods (see ADDRESSES). Please submit e-mail comments to Please also include “Attn: Barred Owl EIS” in your e-mail subject header and your name and return address in the body of your message. If you do not receive a confirmation from the system that we have received your e-mail message, contact us directly by calling our Oregon Fish and Wildlife Office at phone number 503-231-6179. Please note that the e-mail address will be closed at the end of the public comment period.

Public Availability of Comments

Before including your address, phone number, e-mail address, or other personal identifying information in your comment, you should be aware that your entire comment—including your personal identifying information—may be made publicly available at any time. While you can ask us in your comment to withhold your personal identifying information from public review, we cannot guarantee that we will be able to do so. Comments and materials we receive will be available for public inspection, by appointment, during normal business hours at the Oregon Fish and Wildlife Office (see ADDRESSES).

References Cited

A complete list of all references cited herein is available upon request from our Oregon Fish and Wildlife Office (see FOR FURTHER INFORMATION CONTACT).

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Dated: December 3, 2009.

David Wesley,

Deputy Regional Director, U.S. Fish and Wildlife Service, Region 1, Portland, Oregon.

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[FR Doc. E9-29447 Filed 12-9-09; 8:45 am]