At a Glance Hot weather over Memorial Day weekend led to a massive die-off of anchovies in Puget Sound.

The fish died from a lack of oxygen, scientists say.

Thousands of anchovies washed up on the shores of Puget Sound in Washington last week after hot weather over the Memorial Day weekend changed the feeding patterns of the fish, state wildlife officials say.

The fish reportedly began to wash up on beaches at Case Inlet near Belfair, Washington, early last week and continued to do so throughout the week , KOMO News reported.

"It's sad. It's really sad," resident Kristen Wiseman told KOMO of the scores of dead fish scattered on the beach near her home.

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State fish biologists told the news station the hot weather last weekend prompted the fish to swim closer to the shore to feed on plankton. When the tide went out, the anchovies became trapped and died from a lack of oxygen.

<img class="styles__noscript__2rw2y" src="https://dsx.weather.com//util/image/w/screen_shot_2017-06-05_at_12_0.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0" srcset="https://dsx.weather.com//util/image/w/screen_shot_2017-06-05_at_12_0.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 400w, https://dsx.weather.com//util/image/w/screen_shot_2017-06-05_at_12_0.jpg?v=ap&w=980&h=551&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 800w" > Scores of dead anchovies washed ashore in Case Inlet, near Belfair, Washington, last week. (Courtesy KOMO News) (Courtesy KOMO News) "And so now it's lots of fish using up lots of oxygen trapped in shallow rapidly warming water and effectively what happens is the fish get cooked," Dr. Dayv Lowry, a Department of Fish and Wildlife research scientist, told KOMO.

According to weather.com meteorologist Chris Dolce , temperatures in the area reached the mid-80s over the holiday weekend, which is about 20 degrees warmer than average for the area in late May.

The large fish die-off is not new or alarming, biologists told KOMO, adding the die-off will not affect the huge population of anchovies that live in the sound.

Other species in other areas of the sound aren't faring as well. According to the Seattle Times, Seth Book, a biologist with the Skokomish Tribe who has monitored the marine waterway, noted in 2015 several species of marine life are succumbing to low levels of oxygen at depth in Hood Canal.

"It's a dead zone anywhere east of Sister's Point to Belfair, Mason County. There's very low oxygen at depth," said Book, noting die-offs occur every year in the long and narrow Hood Canal, where slow circulation and warmer summer temperatures lead to lower oxygen concentrations in the water.

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