October 8 , 2003 Canadian Common Loons facing threat in Nevada: Walker Lake ecosystem in crisis Walker Lake is a large lake (surface area of 13 000 hectares) at the end of western Nevada’s Walker River. The lake is a terminal sink, which means it has no known surface or ground water outflows. Many Common Loons make a brief stopover on Walker Lake during their spring and fall migration. What is the state of the Walker Lake ecosystem? The Walker Lake watershed is located in the desert, where water is a critical commodity. For generations, water has been diverted from the Walker River for irrigation. The level of Walker Lake has fallen by 46 metres since water diversions started. Currently, water rights exist for 140% of the river’s flow, meaning that no water will reach the lake unless the flow is much greater than normal. There has been a prolonged and continuous drought in the region, and no water has reached the lake for the past two years. High levels of evaporation combined with an absence of water inflows are acting to concentrate the total dissolved solids, which increases salinity in the lake. Salinity has continued to increase as the lake’s water level has continued to drop. How does this threaten the migrating loons? High salinity in the lake is having a severe effect on the fish community. Tui chub, the primary food source for the loons, can no longer reproduce. The tui chub that do remain in the lake will soon be too large to be consumed by the loons. If the Walker Lake fish community dies, there are no other lakes in the region that could support a similar number of loons, because none have the required fish. What is the Canadian connection? Common Loons breed on lakes in Canada’s boreal and mixed forests. They spend their winters at sea along the Pacific or Atlantic coasts. Along their migration route during the fall and spring they make brief stops at inland lakes, where they rest and refuel on fish. Walker Lake is one such stopover destination where up to 1,500 Common Loons are found during April and October every year. This is likely the largest congregation of Common Loons in the western United States. In 1998, five Common Loons were radio-marked on Walker Lake. All five were tracked to their summer breeding grounds in central Saskatchewan, an area approximately 150 kilometres northeast of Lloydminster. Because the breeding range of Common Loons is almost entirely within Canada, it is very likely that the rest of the Walker Lake loons also return to lakes in western Canada every summer. Walker Lake’s loons are also Canada’s loons. The water management practices on this Nevada watershed have far reaching implications that could affect the western population of loons returning to breed each year on our northern lakes. What you can do – Be an advocate for loon conservation. Get involved in a community project that will help to protect lakes where loons breed. Add your voice to calls for better management of the Walker Lake watershed by writing to US Senators John Ensign and Harry Reid, Representative Jim Gibbons, Nevada Governor Kenny Guinn, and U.S. Fish & Wildlife Manager Steve Thompson and informing them how current management practices are threatening our shared loons. Senator John Ensign, Suite 738 Senator Harry Reid, Suite 902 Representative Jim Gibbons, Suite 502 400 S Virginia St. Reno, NV 89501 Governor Kenny Guinn Executive Chambers Capitol Complex Carson City, NV 89710 Governor Kenny Guinn Executive Chambers Capitol Complex Carson City, NV 89710 Steve Thompson, Manager U.S. Fish & Wildlife Service California – Nevada Operations 2800 Cottage Way, Room W-2606 Sacramento CA 95825 For further information – Read about the Nevada Important Bird Areas Program. Check out the Lahontan Audubon Society’s Position Paper on Walker Lake/Walker River. See http://www.walkerlake.org for more local information about Walker Lake. For more technical details on changes to the watershed’s ecosystem, see the U.S. Geological Survey’s fact sheet entitled Water Budget and Salinity of Walker Lake, Western Nevada.