Scientists and volunteers at the California Institute of Mammal Research and Academy of Science are preparing to perform an operation on the body of a gray whale washed ashore on San Francisco Bay on April 23 at Tiburon, California.
In California, in less than two months, the bodies of nine gray whales were found in San Francisco Bay. This is an extremely unusual series of deaths that experts say are mainly due to boat attacks or malnutrition status of this mammal.
Pádraig Duignan, chief pathologist at the Mammal Research Institute, said: "This is a phenomenon very bnormal. On an average of one year, we only discovered one to three gray whales in this season. This is three times that time in less than two months."
Among them, four whales were identified by the Mammal Research Institute as malnutrition. Four other children died due to ship attacks. Left one, discovered on April 30, with death still a mystery.
Most recently, on May 6, at the Ocean Coast in San Francisco, a female whale was also identified as the cause of death due to boats.
Duignan said: "This gray whale seems to have a software injury. Previously, it was in poor health, most of the muscles were atrophic and not fat, unlike the condition of other females living in the area and at the same time of the year."
Mr. Duignan said: “The Marine Mammal Research Institute has worked with organizations such as the National Oceanic Atmospheric Administration, California Academy of Sciences and scientists in other areas of California to track fish life. elephants and animals living in the Pacific Ocean. From here, biologists realized the worrying malnutrition of the whale population this year."
In Washington, 13 dead whales washed up on state beaches since April and are also suspected of lack of food leading to malnutrition.
Gray whales migrate south in winter to breed in Baja California, Mexico, before returning to Alaska along the coast in the spring. They travel through California waters between December and January and again in April and May. Their annual journey is up to 17,700 km, the longest of any migration of any Whales.
The main food of gray whales is the small invertebrates that live in ocean sediments and their feeding time is largely in summer in Alaska. But this year, by the time they returned to the Gulf in the spring, whales were exhausted from hunger. Scientists have observed that they feed in San Francisco Bay, an unprecedented thing.
Moe Flannery, manager of the collection of birds and mammals at the California Academy of Sciences, said: "The most appropriate hypothesis is that last summer, these whales were in Alaska and didn't find enough bait to store for the migration season.". She also said the partners in Baja California reported that the whales had migrated later, had fewer children, and that they gave birth to babies in the ocean, different from every year, in the ferries all.
Last Monday, the same day that the latest whale beach discovered on California beach, the United Nations announced a startling report that as many as 1 million species are at risk of extinction because of human activity. .
California's ocean climate is changing and the warmer Alaska could make some changes to this species this year. Mr. Duignan said they need to conduct more research to understand the root cause of whale death. He said: "The whales killed by stabbing boats are a direct impact from humans. Other children are malnourished with unknown causes. But the global warming effect could be the reason for this mammal gradually growing."