0:00:00.8 John Sheehan: This is Dive In with NOAA Fisheries. I'm John Sheehan, back with a roundup of news, happenings, and goings-on from around the agency. Because as we've mentioned, the work accomplished at NOAA Fisheries spans oceans, regions, coasts, and time zones, and it is simply not possible to get to everything in our usual podcast episodes. These roundups let us check in a little more informally, and hear about developments happening all over the country. So, we'll start on the West Coast with a bit of good news, the closure of an unusual mortality event for the Eastern North Pacific gray whale. From 2019 to 2023, an increase in strandings of these gray whales led to the UME being declared, which happens when a marine mammal population experiences significant and unexplained deaths.

0:00:50.9 JS: But now, in consultation with the working group on marine mammal unusual mortality events and outside experts, NOAA Fisheries has declared that UME over. Hooray! Staying in the North Pacific, new research has revealed that two types of well-known killer whales that were once considered part of the worldwide species or Sinus orca are actually two separate species. Through genetic, physical, and behavioral evidence, scientists have concluded that resident and bigs killer whales are each, in fact, their own species. Resident killer whales maintain tight-knit family pods and prey on salmon and other marine fish. Biggs killer whales roam in smaller groups, preying on other marine mammals such as seals and whales. Remember, killer whales actually belong to the dolphin family. They have evolved as genetically and culturally distinct groups, which occupy different niches in the same northwest marine ecosystem. Barbara Taylor, a former NOAA fisheries marine mammal biologist, put it this way, "They're the most different killer whales in the world, and they live right next to each other. And they see each other all the time. They just do not mix." Speaking of new species, Dr. Catherine Bemis of NOAA Fisheries National Systematics Laboratory and her collaborators recently described a new fish species, Amelichthys Pepilatus, or the Pepilated Redbait.

0:02:19.8 JS: These deepwater species can be found in warm, tropical waters and are usually bright shades of red, orange, and pink. This discovery was made at a Philippine fish market, where the fish was originally thought to be a golden Redbait. But its genetic sequences didn't match up with that identification. It turns out there were additional anatomical differences as well. And though there are still many unknowns about the species, as one scientist put it, "It underscores how much we still have to learn about marine biodiversity." Early March marked seal and sea lion week, and the Pacific Islands Regional Office announced the first Oahu-born Hawaiian monk seal pup of 2024. It was named Makana with help from local fifth graders at the Kahuku Elementary School. We recently spoke to scientists Jamie Thompson and Tracy Mercer about Hawaiian monk seal pups for this podcast. You can find it at our website, fisheries.noaa.gov, and learn more about seal and sea lion conservation efforts, such as the John H. Prescott Marine Mammal Rescue Assistance Grant Program. It supports our seal and sea lion conservation partners around the nation, such as the Marine Mammal Center in California and the Alaska Sea Life Center. Between 2001 and 2023, the program has awarded over $75 million to NOAA's conservation partners.

0:03:45.7 JS: A new study out of the Alaska Fisheries Science Center is expanding scientists' understanding of how to use eDNA. Environmental DNA, or eDNA, refers to analyzing water samples and using genetic material to detect species in the ocean. But many variables can affect how that eDNA is dispersed through the water. Variables like temperature, salinity, depth, currents can all make it difficult to interpret results and determine the location of animals relative to those eDNA detections. In a recent study, scientists examined the influence of distance and tides on the distribution and concentration of eDNA, which is helping scientists refine their understanding of this powerful tool. An update on another huge habitat conservation story that we covered on this podcast last summer. The Klamath River is reshaping itself as recent precipitation is flushing decades of sediment that had accumulated behind dams. With the reservoirs behind the dams now empty, the river is transporting the sediment downstream toward the ocean while it's still wet and mobile. Further flushing from water released from dams upstream will create a flow that peaks at approximately double the current river volume, making the next few months the best opportunity for the river to flush out that sediment that had built up over 60 to 100 years. The flushing will jumpstart recovery of the once prolific salmon-producing river's natural configuration and channels.

0:05:16.1 JS: It's an early step in the nation's largest ever dam removal and river restoration project. And finally, a quick note from Topsfield, Massachusetts, where the Friends of Hood Pond, a community nonprofit and other partners, have made real progress in helping their local watersheds and are serving as a model for how other communities can approach habitat conservation. Involving state and federal grants and grassroots fundraising. After years of work, 2023 saw a period of no invasive species in the pond, and the improved water quality has brought back wildlife like bullfrogs and eagles to prey on the fish. You can read all about it at our website, fisheries.noaa.gov, where you can also find past episodes of our podcast, or sign up for a newsletter. Just recently, NOAA Fisheries launched The Shift, a newsletter focusing on climate change. Some recent stories include how whales contribute to carbon capture, how warming waters are affecting algae blooms and the entire food web in the Bering Sea, and how agency efforts to combat the impacts of climate change are getting help from the Bipartisan Inflation Reduction Act. I'm John Sheehan, and this has been Dive in with NOAA Fisheries.