ANCHORAGE, Alaska (AP) Federal scientists have determined that extremely low levels of crude oil spilled by the Exxon Valdez caused heart problems in embryonic fish, a conclusion that could shape how damage is assessed in other major spills. In a study published Tuesday in the online journal Scientific Reports, researchers from the National Oceanic and Atmospheric Administration found that embryonic herring and salmon exposed to low levels of crude oil developed misshapen hearts. Metabolically, they're different," said John Incardona, a research toxicologist at the Northwest Fisheries Science Center in Seattle. "They cant grow as well. They cant swim as fast."The defects and subsequent vulnerability may explain why the herring population crashed several years after the spill in Alaska's Prince William Sound and has not recovered, scientists said. The 986-foot Exxon Valdez struck a charted Bligh Reef at 12:04 a.m. March 24, 1989, spilling 11 million gallons of crude oil. At the time, it was the largest spill in U.S. history. Oil extensively fouled shoreline, spawning habitat of herring and pink salmon, the two most important commercial fish species in Prince William Sound. Fish larvae sampled close to high concentrations of oil were found with abnormalities. Little was known in the early 1990s, however, about the effects of low-level crude oil exposure on fish in early life stages, according to the study. Pink salmon declined but recovered. The herring population collapsed three to four years after the Exxon Valdez ran aground and the role of the spill, NOAA Fisheries scientists acknowledged, remains controversial. The silvery fish is a key species because it is eaten by salmon, seabirds, and marine mammals from otters to whales. Four years after the spill, the estimated herring population based on modeling shrunk from 120 metric tons to less than 30 metric tons. For the study, the scientists temporarily exposed herring and salmon embryos to low levels of Alaska North Slope crude oil before placing them back into clean water. The threshold for harm in herring was remarkably low, Incardona said. Herring, in particular, are sensitive," in part because their eggs and yolk sacs are so much smaller. After exposure, scientists transferred fish embryos to clean water, let them grow for seven to eight months, and tested them in swim tunnels. Scientists used swimming speed as a measure of cardiorespiratory fitness. Fish exposed to the highest levels of oil swam slowest, likely making them easier targets for predators. He compared the damaged herring to infant children born with heart defects. The child doesn't grow well. Its called failure to thrive, a condition that can be corrected by a heart surgeon. That doesn't happen with fish," he said. According to water samples collected in Prince William Sound during the 1989 herring spawning season, 98 percent of the samples had oil concentrations above the level that caused heart development problems among herring in the study. Juvenile salmon with heart defects, swimming more slowly and not pumping blood as efficiently as an unharmed fish, would be more vulnerable to predators and disease. It's not much of a leap, he said, to conclude that more juvenile mortality would affect how many herring survive to be spawning adults. The findings should contribute to more accurate assessments of other spills, such as the Deepwater Horizon disaster, which replaced the Exxon Valdez spill as the largest in U.S. history. And not just other spills," Incardona said. "For us down here in Puget Sound, one of our big concerns is just urbanization and the little, tiny oil spills that happen every day as nonpoint source pollution. Certainly for both large spills and everyday chronic pollution from fossil fuel use are potentially producing the same kinds of effects."Alan Jeffers, media relations manager for Exxon Mobil Corp., said the company had no comment on the study.

Where is the questions I don’t see questions

what are greenhouse gases and what do they do

How are scientists monitoring and studying the effects on the herring?

science help mixtures giving brainly

Can someone please help me understand why i feel like no one cares and why i feel the need to cry my self to sleep or why i feel like the whole world is aginst me

Which method of separation of mixtures is vital to life on earth?

filtration, sifting, evaporation, or distillation?

Which one describes Cryosphere A. A portion of Earth's interior, rocks and minerals, landforms, and the processes that shape Earth's surface B. All water on Earth: ocean surface water, groundwater, and glaciers; made of a limited number of elements and it is primarily comprised of oxygen and hydrogen, two elements in pure water C. Places on Earth where the water is frozen all the time D. The layers of gas surrounding planet Earth, held in place by gravity and composed of a limited number of elements, primarily nitrogen and oxygen

The ocean can be considered one massive food web. Remove one link from this food web and it can have devastating effects on the ecosystem. Why is it important that scientists and researchers study declines like this?

Please provide an example of the biosphere, hydrosphere, and geosphere interacting...

Predict: Will a 1500 kg car moving at the same speed as the tennis ball have more momentum or less? (i think more)
Calculate the momentum of the car and record it here.

the train is travelling at 15 m/s. It accelerates at 3 m/s² for 20 seconds. How far does the train travel in this time?

Rubber is a type of _________.
radiator
distributor
insulator
conductor

SCIENCE:
In 2-3 complete sentences, explain how a satellite goes into orbit remains in orbit in your own words.

Use the "RAP" method to answer this question:

Restate the question
Answer the question
Prove your answer citing textual evidence from the course.
Don't forget to proofread your answer.

The law of conservation of energy states that energy can neither be created nor destroyed. What does “conservation” mean in this law? I need the answer quickly

Someone help me this ASAP~!

Help me ASAP (this is science ;-;)

How are scientists monitoring and studying the effects on the herring?

How are gas particles arranged in a container?
1.Loosely arranged
2.Neatly organized
3.Tightly packed
4.Far apart

Which property of gas particles allows them to spread around in a closed container?
1.Diffusion
2,Density
3.Motion
4.Size

I need help with this problem please asap

A car is rolling south at 8 miles per hour, and a man pushes a car north at ten miles per hour. What is the resultant vector on the car? a. 2 miles per hour north b. 2 miles per hour south c. 18 miles per hour north d. 18 miles per hour south

Ella has a mass of 56 kg, and Tyrone has a mass of 68 kg. Ella is standing at the top of a skateboard ramp that is 1.5 meters tall. Which conclusion is best supported by the given information?

What are the properties of the layers of the Earth atmospheres

What is normal hearing?

I need help with this ASAP please :)

The lowest point in the state of Louisiana is New Orleans. The city’s elevation is 8 feet below sea level. Write the elevation of New Orleans as an integer.

Which of the following are conductors? (Select all that apply).
rubber
metals
plastic
tile
carpet