Happens every time:
https://nautil.us/where-have-all-the....1669683207578
Cause:
As he descended and the seafloor came into view, Braxton Dew witnessed a phenomenon few others had ever seen: a mountain of king crabs. There were some 9,000 of them, towering above his head once he reached the seabed. He checked the depth gauge: 75 feet. He captured a photograph.
...
In 1996, Dew used the photo to help demonstrate to NOAA administrators that the survey methods they used to estimate adult king crab populations were flawed.1 It was too easy to pull the sampling net through an aggregation and extrapolate that highly localized density to an entire region. If this occurred, the population estimates used by government managers of Alaska’s king crab fishery could be inaccurate.
According to Dew, the evidence he presented caused turmoil inside NOAA. He was transferred from Kodiak to Seattle; underwater crab research conducted by the agency declined sharply. He remained there for 12 years without assignment, waiting to publish his final manuscripts in the NOAA Sea Grant Collection, in which he laid out evidence suggesting that king crab management should better account for factors like social behavior and habitat preference.2 Some of the papers would spend over a decade stalled in review until his former bosses retired in the late 2000s.
Effect:
When the National Oceanic and Atmospheric Administration announced the first-ever cancellation of the Bering Sea snow crab season in October—and extended the closure of the king crab fishery—explanations were thin. Headlines relayed what the government had gathered: Nearly 11 billion crabs had, effectively, disappeared.