AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS

1. Tropical rivers are increasingly being altered by hydropower dams. In Costa Rica, more than 30 hydropower plants were built during the 1990s and more dams are being proposed. Hydropower dams currently provide more than 80% of electricity consumed by the country’s 4 million residents, yet most of Costa Rica’s hydropower potential remains untapped. 2. Ecological consequences of dams in Costa Rica stem primarily from river fragmentation, stream de-watering, and downstream hydrological alterations. Dams affect distribution and abundance of aquatic biota, especially migratory species. Cumulative effects of multiple dams on individual river basins, especially in the northern part of the country, are also of concern but have not been adequately documented. 3. In light of recent hydropower development, we recommend conservation strategies that protect remaining free-flowing rivers, call for assessment of ecological impacts of dams on a broader scale, encourage research on aquatic systems and sustainable hydropower technologies, and promote the development of methods for estimating environmental flows for Costa Rican rivers. Copyright # 2006 John Wiley & Sons, Ltd.

[1]  Charles F. Rabeni,et al.  Sediment in Streams: Sources, Biological Effects, and Control , 1997 .

[2]  Robert Bacon,et al.  Public policy for the private sector , 1995 .

[3]  M. Freeman,et al.  Regional Effects of Hydrologic Alterations on Riverine Macrobiota in the New World: Tropical–Temperate Comparisons , 2000 .

[4]  C. Pringle,et al.  Use of both benthic and drift sampling techniques to assess tropical stream invertebrate communities along an altitudinal gradient, Costa Rica , 1998 .

[5]  C. Rica..  Use of both benthic and drift sampling techniques to assess tropical stream invertebrate communities along an altitudinal gradient , , 2010 .

[6]  C. Pringle,et al.  Transforming tropical rivers : an environmental perspective on hydropower development in Costa Rica , 2006 .

[7]  G. A. Cruz.  Reproductive biology and feeding habits of cuyamel, Joturus pichardi and tepemechín, Agonostomus monticola (Pisces; Mugilidae) from Rio Plátano, Mosquitia, Honduras , 1987 .

[8]  Matthew Taylor.  Electrifying Rural Guatemala: Central Policy and Rural Reality , 2005 .

[9]  F. Triska,et al.  Emergent biological patterns and surface-subsurface interactions at landscape scales , 2000 .

[10]  E. A. Greathouse,et al.  Conservation and management of migratory fauna: dams in tropical streams of Puerto Rico , 2006 .

[11]  B. B. Yoshioka,et al.  High Dams and Marine‐Freshwater Linkages: Effects on Native and Introduced Fauna in the Caribbean , 1998 .

[12]  J. March,et al.  Damming Tropical Island Streams: Problems, Solutions, and Alternatives , 2003 .

[13]  Christoph Humborg,et al.  Effect of Danube River dam on Black Sea biogeochemistry and ecosystem structure , 1997, Nature.

[14]  Mary C. Freeman,et al.  Ecological consequences of hydropower development in Central America: impacts of small dams and water diversion on neotropical stream fish assemblages , 2006 .

[15]  Cooperation between a small private hydropower producer and a conservation NGO for forest protection: the case of La Esperanza, Costa Rica , 2002 .

[16]  Michel Pimbert,et al.  What Are We Learning from Experiences with Markets for Environmental Services in Costa Rica?: A Review and Critique of the Literature , 2003 .

[17]  F. Scatena.  A survey of methods for setting minimum instream flow standards in the Caribbean basin , 2004 .

[18]  Jan Cornelius Schmidt,et al.  Dams and rivers: a primer on the downstream effects of dams , 1996 .

[19]  W. Graf.  Dam nation: A geographic census of American dams and their large‐scale hydrologic impacts , 1999 .

[20]  G. Lanza,et al.  Silenced Rivers: The Ecology and Politics of Large Dams , 1996 .

[21]  T. Hamazaki,et al.  THE ROLE OF OMNIVORY IN A NEOTROPICAL STREAM: SEPARATING DIURNAL AND NOCTURNAL EFFECTS , 1998 .

[22]  Philip M. Fearnside,et al.  Hydroelectric Dams in the Brazilian Amazon as Sources of ‘Greenhouse’ Gases , 1995, Environmental Conservation.

[23]  Simon A. Levin,et al.  Lost linkages and lotic ecology: rediscovering small streams. , 2001 .

[24]  J. Stanford,et al.  The serial discontinuity concept of lotic ecosystems , 1983 .

[25]  Wcd.  Dams and development: A new framework for decision-making , 2000 .

[26]  A. Ndiaye.  POVERTY ASSESSMENT REPORT , 2006 .

[27]  J. March,et al.  EFFECTS OF A LOW‐HEAD DAM AND WATER ABSTRACTION ON MIGRATORY TROPICAL STREAM BIOTA , 1999 .

[28]  C. Nilsson,et al.  Alterations of Riparian Ecosystems Caused by River Regulation , 2000 .

[29]  Peter H. Gleick,et al.  Environmental consequences of hydroelectric development: The role of facility size and type , 1992 .

[30]  C. Nilsson,et al.  Fragmentation and Flow Regulation of River Systems in the Northern Third of the World , 1994, Science.

[31]  C. Revenga,et al.  Fragmentation and Flow Regulation of the World's Large River Systems , 2005, Science.

[32]  C. Goldman,et al.  Dams and development in the tropics: the role of applied ecology. , 1990 .

[33]  Arthur C. Benke,et al.  A Perspective on America's Vanishing Streams , 1990, Journal of the North American Benthological Society.

[34]  Kirk O. Winemiller.  ASPECTS STRUCTURELS ET FONCTIONNELS DE LA BIODIVERSITÉ DES PEUPLEMENTS DE POISSONS. , 1995 .

[35]  R. Barnes.  AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS , 1999 .