WYOMING – Over the past 60 days, temperatures in parts of northern and southwestern Wyoming have reached 8 degrees above normal. And it’s not just highs.
If a city is used to, say, nocturnal troughs in the mid-1950s, it experiences troughs that never drop below 60 and highs into the 1990s, said Chris Jones, a meteorologist with the National Weather Service at Riverton.
“We don’t see the relief that we used to have at night, and that is often what becomes more noticeable to people,” Jones said. “If it doesn’t go down to 66, for example, and it’s at 71, it gives the next day a boost and dries up the soil more, then it will continue to allow the temperature to rise a little more each day.” .
This summer’s record or near record temperatures, combined with low winter snowfall and unusually low river flows, are prompting fisheries and land managers across the state to issue serious warnings to anglers. The fish are dying and fishing in the heat of the day will only make it worse, they say.
Some of these warnings come in the form of recommendations, and others involve changes in fishing regulations. In Yellowstone National Park, for example, fishing is now prohibited after 2 p.m. The park also has a warning for those who do not wish to join.
“Your cooperation will protect the park’s fisheries and may prevent the need to ban fishing at any time of the day on certain rivers and streams if conditions worsen,” the park said in a press release.
Warm river temperatures are not unusual for Wyoming in late summer. Fishery biologists often recommend in mid-August or late August that anglers be more careful when fishing with a release or only in the early hours of the day.
But the conditions this summer were more severe than usual.
Not only have temperatures been well above average in many places, but rainfall has also been scarce, especially in the northern and western parts of the state, Jones said.
In early July, places like Rock Springs were seeing less than a fifth of normal precipitation since April 1. The ground is so dry that even when the rain has fallen recently, very little is absorbed by the earth, Jones said. In Rock Springs, for example, when more than an inch of rain fell in late July, the dangerous combination of downpour and sunburnt soils created urban flooding.
“The ground is not receptive,” Jones said. “It’s like concrete, you get a lot more runoff.”
The situation could have serious consequences for a number of wildlife species, including deer and American antelope if the drought persists. Shrubs and plants do not grow, making it difficult for some animals to get enough food before winter.
But these are the fish that are of greatest concern to biologists right now.
Trout are cold water animals that need high levels of oxygen. The hotter the water, the lower the oxygen.
Prolonged water temperatures above 75 degrees Fahrenheit are dangerous for trout, and anything above 80 degrees is lethal, said Hilda Sexauer, Pinedale fisheries supervisor at the Wyoming Game and Fish Department.
Add to that the stress of being caught, fought and released, and many fish won’t stand a chance, she said.
This is why Yellowstone has placed restrictions on fishing and Game and Fish has sent out several emails asking fishermen to think about trout before heading out to the water.
And according to forecasts, conditions are unlikely to improve.
Temperatures are expected to be warmer than normal with below average precipitation through October, Jones said.
“Can you get a week out of the ordinary?” Absolutely, ”Jones said, but added that the overall outlook is hot and dry.
For many anglers, the question for the rest of the summer becomes: should they fish?
The answer is nuanced, say fish biologists.
Game and Fish doesn’t ban fishing, even in the afternoon, but it recommends anglers not to catch and release fish after 2 p.m. in the warmer, lower parts of the state. Department biologists also ask fishermen to land the fish as quickly as possible and keep them in the water.
Other recommendations include avoiding squeezing the fish or putting your fingers under its gills, and consider using barbless hooks for faster release, and flies or artificial lures if you plan to release. Fish.
Biologists also encourage anglers to assess the health of a fish before releasing it.
“If a fish is exhausted and cannot stand upright, and if the regulations allow it, consider taking it for supper because the fish is unlikely to survive,” the Game and Fish recommendations state.
The water is hottest in the afternoon and evening. Sunset fishing is much more dangerous for trout than sunrise, even though the air temperature is cooler.
Anyone fishing in the heat of summer should also consider bringing a thermometer to measure water temperature, said Anna Le, aquatic biologist and educator in Yellowstone.
There is no such thing as a “safe” magic temperature for trout fishing. Species, current speed, river structure, water quality, and a myriad of other factors all contribute to survivability. However, many experts and fishermen advise calling it a day when the water temperature reaches 68 degrees.
The showed up on the banks of the rivers of Yellowstone ready to fish and turned around because the water temperature was just too high to ethically catch and release fish, she said. .
“For me, the concern is to stress them out, especially if you enter their habitat or hang them when there are low levels of oxygen in the water,” she said. She is also concerned about the introduction of bacteria that are more able to thrive in warmer temperatures.
Anglers may also consider catching warmer water fish such as sunfish, bass, catfish or carp.
To Casper, Game and Fish announced the death of fish at Yesness Pond. The heat may well stress and kill trout in small, low-lying creeks and lakes around the region, including Deer, Boxelder and LaPrele creeks, biologist Matt Hahn said in another heat-related press release.
Green River angler and Trout Unlimited project manager Nick Walrath has switched to targeting carp in places like the Flaming Gorge Reservoir or even in the Green River itself because the water is too hot to catch and release the trout, he said.
Heading to the cooler waters of high mountain streams and lakes is also safe. Some mountain ranges in Wyoming, including the Snow Capped Range in southeastern Wyoming, still have snowmelt and feeding lakes, keeping temperatures very cold to responsibly catch and release.
This winter can bring relief, Jones said. It’s a La Niña year, which typically brings above normal precipitation over the northwestern part of the state in winter and an equal chance of being above, average, or below for the rest of the state.
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