Special Section Managing Aquatic Species of Conservation Concern in the Face of Climate Change and Invasive Species FRANK J. RAHEL, ∗ BRITTA BIERWAGEN,† AND YOSHINORI TANIGUCHI‡ ∗ Department of Zoology and Physiology, Department 3166, 1000 East University Avenue, University of Wyoming, Laramie, WY 82071, U.S.A., email frahel@uwyo.edu †Global Change Research Program, National Center for Environmental Assessment, U.S. EPA–ORD (MC 8601P), 1200 Pennsylvania Avenue NW, Washington, D.C. 20460, U.S.A. ‡Department of Environmental Science and Technology, Meijo University, Tenpaku, Nagoya, Aichi 468-8502, Japan Abstract: The difficult task of managing species of conservation concern is likely to become even more challenging due to the interaction of climate change and invasive species. In addition to direct effects on habitat quality, climate change will foster the expansion of invasive species into new areas and magnify the effects of invasive species already present by altering competitive dominance, increasing predation rates, and enhancing the virulence of diseases. In some cases parapatric species may expand into new habitats and have detrimental effects that are similar to those of invading non-native species. The traditional strategy of isolating imperiled species in reserves may not be adequate if habitat conditions change beyond historic ranges or in ways that favor invasive species. The consequences of climate change will require a more active management paradigm that includes implementing habitat improvements that reduce the effects of climate change and creating migration barriers that prevent an influx of invasive species. Other management actions that should be considered include providing dispersal corridors that allow species to track environmental changes, translocating species to newly suitable habitats where migration is not possible, and developing action plans for the early detection and eradication of new invasive species. Keywords: aquatic invasive species, climate change, dispersal corridors, habitat improvement, imperiled species, invasive species effects, range shifts, species of conservation concern, species translocation Manejo de Especies Acu´ aticas de Inter´ es para la Conservaci´ on ante el Cambio Clim´ atico y las Especies Invasoras Resumen: Es probable que la dif´ ıcil tarea de manejar especies de inter´es para la conservaci´ on se vuelva m´ as retadora debido a la interacci´ on del cambio clim´ atico y las especies invasoras. Adicionalmente a los efectos directos de la calidad del h´ abitat, el cambio clim´ atico propiciar´ a la expansi´ on de especies invasoras hacia nuevas ´ areas y magnificar´ a los efectos de especies invasoras ya presentes mediante la alteraci´ on de la dominancia competitiva, el incremento de las tasas de depredaci´ on y el incremento en la virulencia de enfermedades. En algunos casos, especies parap´ atricas pueden expanderse hacia h´ abitats nuevos y producir efectos perjudiciales que son similares a los especies invasoras no nativas. La estrategia tradicional de aislar especies en peligro en las reservas puede ser inadecuada si las condiciones del h´ abitat cambian m´ as all´ a de los rangos hist´ oricos o de manera en que favorezcan a las especies invasoras. Las consecuencias del cambio clim´ atico requerir´ an de un paradigma de manejo m´ as activo que incluya la implementaci´ on de mejoramiento del h´ abitat que reduzca los efectos del cambio clim´ atico y la creaci´ on de barreras de migraci´ on que eviten el influjo de especies invasoras. Otras acciones de manejo que deber´ ıan ser consideradas incluyen corredores de dispersi´ on provisionales que permitan que las especies rastreen los cambios ambientales, la translocaci´ on de especies a h´ abitats reci´en adecuados donde la migraci´ on no es posible, y el desarrollo de planes de acci´ on para la detecci´ on y erradicaci´ on temprana de especies invasoras nuevas. Paper submitted October 23, 2007; revised manuscript accepted January 14, 2008. 551 Conservation Biology, Volume 22, No. 3, 551–561 C 2008 Society for Conservation Biology DOI: 10.1111/j.1523-1739.2008.00953.x