Sometimes nature throws a curveball.
This time it’s from the grebes, a graceful water bird that has taken advantage of conditions at Lake Hodges to begin nesting at an unexpected time after a two-year hiatus.
Sadly, this ball game has been complicated by several umpires with different rule books and it looks like the grebes may have lost the game.
Lake Hodges is a domestic water storage facility, regulated by the state of California. The California Department of Fish and Wildlife oversees grebes, and then there is the San Diego City Utilities Department that manages the water.
The San Diego County Water Authority is also involved in controlling water pumping schedules resulting from demands from downstream water districts.
No one disputes the need for domestic water, but both state and federal law protects wildlife, and Lake Hodges is a prime nesting ground for the grebes, when conditions are right.
In the past, there was a disconnect between the various agencies and grebe nesting suffered as a result.
Grebes build their nests on floating platforms attached to plants growing in shallow portions of the lake. If water levels rise or fall too far, nests can either be flooded or eggs and chicks die if parent birds cannot access the nests.
That’s what happened during peak nesting season in 2019 when the state, citing safety concerns mandated that Lake Hodges water levels never exceed 20 feet below the spillway. Water levels were lowered, inhibiting the natural habitat for grebe nesting. The result was the absence of a nesting colony for the past two seasons.
The curveball this year was thrown when the Clark’s and Western grebes took advantage of ideal conditions and began nesting in late July.
This is not typical. Normal grebe nesting begins in late spring.
Sometime in June water levels were lowered for pump maintenance, allowing vegetation to grow in the mudflats at the east end of the lake. When water was restored, grebes took advantage of the ideal habitat and began nesting.
The nesting cycle is a sensitive time, less than a month in length, when water levels should be stabilized.
A few weeks ago, I spotted more than 100 active nests, and a few fuzzy chicks that had hatched. Once chicks hatch, they climb onto the back of parent birds until they can swim and feed on their own.
But again, water levels fluctuated, and it appears that most of the nests with unhatched eggs have failed.
One of those most in tune with the grebe nesting cycle is Brian Caldwell, an active birder who operates Lake Hodges Photo Tours. He lives in Del Dios, on the shores of Lake Hodges and he daily monitors what’s going on with the birds, either from a boat or along trails when the lake is closed to boating.
He sounded the alarm recently when discovering that most of the nests were high and dry.
A nest with an abandoned egg because of reduced water levels.
(Courtesy of Lake Hodges Photo Tours)
Additionally, because of reduced water levels, many nests close to shore became accessible to predators who were eating the eggs.
“I saw a bobcat enjoying a buffet of grebe eggs,” Caldwell said.
Despite promises from water agencies, Caldwell feels the 2021 opportunity grebe nesting cycle is a failure.
In response to an inquiry about protecting the nesting grebes, Arian Collins, a public information officer with the city, offered assurance that the reservoir would be maintained at current levels.
“City biologists continue to monitor the grebe population at Hodges Reservoir. The San Diego County Water Authority’s recent storage of extra water at Hodges has created suitable nesting habitat for the grebes and they started building nests and laying eggs a couple of weeks ago.” Collins said. “We don’t expect any nest abandonment due to water level changes.”
Contacted again when the nests appeared to have failed, Collins responded that natural evaporation and operation of County Water Authority’s hydroelectric facility was the reason for the fluctuation but assured that city staff is monitoring the situation.
He added, “Western and Clark’s grebe species that nest at the Hodges Reservoir are not listed by the California Department of Fish and Wildlife as a threatened, endangered or sensitive species.”
Some in the birding community were not happy with that answer.
“Does this imply it’s OK to kill them?” Caldwell asked. “They have knowingly violated the Migratory Bird Treaty Act hundreds of times.”
Senior Environmental Scientist Supervisor Jennifer Turner with DFW said they are looking into the situation.
“The Department has reached out to the City and the Water Authority to see what can be done to resolve issues of grebe nest abandonment at Lake Hodges. We are actively seeking out a solution that will benefit the grebes, the public, and the entities involved,” she said.
Jim Fisher, operations and maintenance director with San Diego County Water Authority, said the agency strives to minimize impacts to the environment.
“Any impacts to the grebes and their nests at Lake Hodges is an unintended consequence of critical water and energy operations,” Fisher said.
CWA did acknowledge that fluctuations of 1 to 2 feet throughout the week can occur because of regional energy needs. Rainfall, runoff, water usage and evaporation can also affect water levels.
At this point, biologists are trying to accurately determine how many nests were lost.
A report by the San Diego Audubon Society suggests there was a 57 percent success rate of nesting grebes, and that there may be more chicks, but they are hard to spot because they nestle into the feathers of adult birds.
Water and energy versus grebes. It should not be an either/or debate.
As future nesting cycles come and go and water levels fluctuate, the focus should be on finding a solution that protects the 23-day grebe nesting cycle while still allowing efficient water delivery.
In the meantime, the game goes on.
And it’s a wonderful game to watch.
The courtship and nesting are a wildlife wonder, and the grebe chicks are certainly at the top of the cute chart.
How sad would it be without these beautiful creatures in our lives?
Trails on the north and south sides of Lake Hodges, west of Interstate 15 give hikers access to the nesting areas and good views of chicks as they hitch rides on the backs of adults.
The lake is currently open to boaters on Wednesdays, Saturdays and Sundays, allowing birders a view from the water; just remember to stay at least 100 yards away from nests.
Hopefully water levels will be stabilized, and next spring will bring another season of nesting at Lake Hodges.
Email ernie@packtrain.com or visit erniesoutdoors.blogspot.com.
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