Western and Clark’s Grebes winter on the coast—where they have been greatly affected by oil spills and gill nets in the ocean—but they migrate inland to freshwater lakes and marshes to breed in the summer.       

Western and Clark’s Grebes build floating nests made of heaps of plant material on top of bottom-anchored floating plants in about 3ft deep of water. Grebe eggs incubate for 24 days and if water levels drop too low then these nests will be abandoned. In shallow water (about 1 foot or less) the grebes and their nests become vulnerable to attack from predators that are able to access the nests in shallower water where the grebes cannot dive if threatened. 

Lake Almanor is considered an “Important Bird Area” providing essential habitat for breeding, wintering, and migratory birds. It is a critical breeding ground in California for Western (Aechmophorus occidentalis) and Clark’s (A. clarkii) Grebes.  Large numbers of Western and Clark’s Grebes are attracted to Lake Almanor because of the fish prey population (mostly pond smelt) and because there is suitable breeding/nesting habitat around the lake. 

In 2019, the Lake Almanor colony had over 700 nests with the potential for hatching 1000 or more young. Before most eggs could hatch, the colony was abandoned, likely due to the rate of drop in water level (the fastest drop rate in the last 7 years) and less than 100 young were hatched.

Clark's and Western Grebes are both considered "climate endangered" species, so with the changing climate they are projected to lose the majority of their summer breeding ranges by 2080. Clark's Grebe are projected to lose 99% and Western Grebe are projected to lose 96% of their current breeding ranges.

PG&E controls the the drop rate on the lake. Studies on Lake Almanor have clearly shown greater success for the grebes with a drop rate less than 0.72 inches per day. In 2019, Almanor dropped at an astounding rate of 1.05 inches per day for most of July-- the highest rate in the last seven years; much higher than PG&E's forecasted rates of 0.42 inches per day through July.

Help urge PG&E to manage water levels at Lake Almanor with drop rates of no more than 0.72 inches per day during critical grebe breeding season (June 25th through September 15th).