Dozens of northern elephant seal pups died during last month’s storms, but there is no evidence that surviving seals have been harmed by agricultural runoff unleashed by the rains, according to marine ecologists and officials at the Point Reyes National Seashore.
Rep. Jared Huffman urged park officials last week to prevent cattle from grazing in areas near seals, concerned that runoff from nearby ranches might have contaminated the water. In response, park superintendent Craig Kenkel released a letter on Monday stating that the park’s seal population “is healthy, successful, and continues to expand every year.”
“There is no evidence of seals being sick or dying except pups that died due to recent strong storms and their inability to swim,” Mr. Kenkel wrote.
Sarah Codde, a marine ecologist who leads the park’s annual seal count, said population numbers have risen since early this year. Though the female and pup counts are slightly lower than this time last year, she said that was expected, given the number of pups that died at the beginning of the season—as many as 50 to 100—after being swept out to sea by storm surge. “And the moms of those pups have probably already left Point Reyes,” she said.
In their most recent count, conducted on Feb. 1, park staff and volunteers tallied about 2,380 seals, including around 1,000 pups. Those numbers were up substantially from a count taken the second week of January, when Ms. Codde’s team counted around 570 adults and 110 pups. Pupping season peaks in late January.
In the aftermath of January’s torrential rains, some individuals raised concerns that runoff from ranches in the park had posed a threat to the health of the seals that arrive each year to mate, give birth and nurse their pups on the peninsula.
In his Jan. 25 letter to Supt. Kenkel, Rep. Huffman expressed particular concern about seals that had been forced from usual pupping areas due to beach erosion and heavy surf. He urged park officials to take whatever steps possible to protect them.
“This would include measures to prevent the seals from hauling out or pupping in areas where there is a need to remediate water quality problems, and measures to temporarily prevent cattle from grazing in areas where the seals are present,” Rep. Huffman wrote.
In response, Supt. Kenkel stated that the park and the Marine Mammal Center conducted pilot tests last year that focused on weaned pups at Chimney Rock and Drakes Beach. The results showed a low incidence of intestinal bacteria and were consistent with ealier studies of elephant seals on the California coast. Point Reyes seals were less likely to test positive for markers associated with fecal contamination than marine mammals along urbanized coastlines.
Under a water quality strategy approved by the California Coastal Commission last year, the seashore agreed to begin regular water quality testing to measure contamination in watersheds near ranches. The park also agreed to team up with the San Francisco Bay Regional Water Quality Control Board to inspect ranches to make sure they were taking precautions to prevent contamination.
Water board and park staff conducted inspections of all the ranches last February, said Laurie Taul, supervisor of the water board’s Agricultural Lands Program. They advised ranchers on ways to control erosion, divert clean stormwater from corrals and ensure that corrals drain to a waste collection system. They returned for a second round of inspections in November to see whether these and other necessary steps had been taken.
Ms. Taul added that several ranches replaced or upgraded their septic systems last year.
Dairy and cattle ranches have been operating in Point Reyes for generations, but some environmental groups believe ranches should not be permitted in the park. Environmentalists and park officials have been litigating the issues, along with concerns about tule elk management. They began negotiations to resolve them last year and are expected to update the court on their discussions in early April.
Robust populations of northern elephant seals migrate along the Pacific coast, making one of the longest journeys of any mammal each year. Last month’s storms struck just as they had begun arriving at their usual Point Reyes pupping spots: South Beach, the Point Reyes Headlands, Chimney Rock and Drakes Beach. Nearly all the seals at the headlands and Chimney Rock sought out safer locations, Ms. Codde said. Those havens included the beach in front of the Kenneth C. Patrick Visitor Center and Horseshoe Pond, along Drakes Beach east of the visitor center.
The largest colony is located along a two-mile stretch of Drakes Beach south of the visitor center.
Northern elephant seals nurse their pups for about one month before heading back to sea. The pups spend another two to three months on shore, practicing their swimming and diving skills before heading off to deeper waters.
The public can view the seals at the historic lifeboat station, the elephant seal overlook and the Kenneth T. Patrick Visitor Center, which is open from 10 a.m. until 4 p.m.