Conserve Wildlife Blog

Archive for the ‘Fish’ Category

Helping Native Brook Trout by Restoring a Stream

Monday, October 5th, 2020

by Nicole Porter and David Wheeler

Brook trout. Photo courtesy of Shawn Crouse.

Many of New Jersey’s streams have been manipulated by being impounded with dams or weirs, or otherwise redirected over time – decreasing their ecological habitat diversity and blocking fish passage for native brook trout and other species. Restoring these streams to a more natural state can greatly benefit wildlife. 

The Land Conservancy of New Jersey, along with assistance from Conserve Wildlife Foundation, Natural Resources Conservation Service, and Urbani Fisheries, worked on a stream restoration project on a highly modified part of stream flowing through the West Brook Preserve in West Milford this summer. This vital 170-acre preserve holds the headwaters of the West Brook, one of the primary sources of water for the Wanaque Reservoir, which provides drinking water for two million New Jerseyans. 

It appears that sometime in the 1950s, part of the West Brook was taken out of the original stream channel and redirected to a channelized ditch that ran alongside it. There were also several culverts installed in the stream (including one that was the size of a small grain silo) which restricted flow and acted as a blockade to fish passage. In addition, one of the unnamed tributaries leading to the mainstream channel had a pond where water was being held back by a weir, resulting in elevated water temperatures. The original channel and tributaries also needed an enhancement of a thalweg, the line of lowest elevation that the stream follows as well as the addition of pools, riffles and runs.

Removal of large instream culvert that blocked fish passage and restricted flow.

A healthy stream should have an established thalweg – a connected floodplain – as well as pools, riffles, and runs. All of these features are important in the function of the stream.  For example, pools provide areas for various aquatic species to seek refuge, while riffles aid in the reoxygenation of the water. 

Tributary to the West Brook one day after streamwork. In the picture above it shows a constructed pointbar which causes the stream to naturally meander and protects the banks.
Tributary to the West Brook one day after streamwork. In the picture above it shows the enhanced pools and riffles.

The ultimate goals of the West Brook project included restoring the native fish habitat, improving the overall water quality, and rejuvenating the macroinvertebrate population. 

The work done to accomplish this included:

  • Restoring the river back to the original stream channel. 
  • Enhancing features along the whole length of the stream.
  • Creating wetland pools out of the old ditch and within the riparian zone. 
  • Removing five culverts and the small weir. 

After the restoration, it appeared some of the site is now suitable for native brook trout, and the project has greatly improved habitat diversity in a stream that flows into a Category One trout production stream. New Jersey Fish & Wildlife and The Land Conservancy will continue to monitor the project.

Nicole Porter is a biologist with Conserve Wildlife Foundation.

Learn more about New Jersey’s Brook Trout here.

Swam with Dinosaurs and Famed for Caviar, Atlantic Sturgeon at risk in New Jersey

Monday, July 27th, 2020

Latest Podcast explores climate change threats to this ‘living fossil’  

by Milena Bimpong

Delaware State University professor Dr. Dewayne Fox and PhD student Matthew Breece weigh an adult Atlantic sturgeon. (Activities authorized under NMFS Permit No. 16507-01). © Delaware State University

A ‘living fossil’ today swims the Delaware River, having survived eons from the days of the dinosaurs through the caviar craze a century ago that nearly wiped it out for its roe, or valuable eggs.

However, as explored in the latest episode of State of Change – Conserve Wildlife Foundation’s regular podcast exploring climate change impacts on New Jersey wildlife –the Atlantic sturgeon faces an abundance of modern threats.

From a historic population of 360,000 adults, “Based on our best estimates, there’s less than 300 in the river. There’s less than 1 tenth of 1% that was there historically,” says Dewayne Fox, a professor of fisheries at Delaware State University. “The loss of one or two adults is a significant loss of spawning potential in the Delaware River.”

Among the largest river fishes in North America, the Atlantic sturgeon can grow up to 14 feet and weigh up to 800 pounds. One sturgeon from New Jersey is believed to have been over 1,000 pounds. The Atlantic sturgeon’s features indicate that their existence can be traced back to millions of years.

Yet that lengthy run was in jeopardy after facing ensuing perils of caviar harvesting and pollution.


2018 Osprey Outlook

Monday, July 30th, 2018
Insight Into Important (Bio)Indicators: Ospreys

by Ben Wurst, Habitat Program Manager

CWF Osprey Banding Apprentice Northside Jim holds a young osprey, 13/K, after banding.

Mid-summer marks the nestling period of nesting ospreys, a coastal raptor, whose diet consists mainly of fish. As a state that’s heavily influenced by its location along the Atlantic Ocean, they play a critical role in our coastal ecosystem. Ospreys are important bioindicators of the health of our coastal waters, through the lens of their prey, where pollutants are biomagnified through the food chain. As we consume many of the same fish, they show the effects of these pollutants long before humans, so the health of their population has implications for our coastal waters and us! (more…)

How Plastic Pollution Impacts Wildlife – And What You Can Do!

Friday, August 19th, 2016

by Corrine Henn, Communication Coordinator

For those of us who call New Jersey home, we’ve all likely witnessed the impact human activities have on our environment and the species who thrive here. Although habitat loss, illegal poaching and invasive species can be equally devastating to an ecosystem, the presence of plastic pollution around our state is a threat that almost every individual can be found personally culpable.

A jellyfish & a plastic cup cover - which is which? It's easy to see how a sea turtle could get confused and accidentally swallow plastic. Photo by Mike Davenport.

A jellyfish & a plastic cup cover – which is which? It’s easy to see how a sea turtle could get confused and accidentally swallow plastic. Photo by Mike Davenport.

Although many forms of pollution impact our native species, the summer months at the Jersey Shore often result in a surge of plastic debris that are left behind or improperly disposed of. Plastic pollution impacts millions of wildlife species globally, and the diverse number of species in New Jersey are no exception.

The plastic pollution that accumulates in our waterways and elsewhere around New Jersey poses a serious threat to native species. Single-use plastic products like plastic bags, bottles, bottle caps, wrappers, straws, and even balloons are not only unsustainable, but particularly dangerous for the animals that may become entangled in them or accidentally ingest them.

Ospreys use trash as nesting material because (sadly) it is a plentiful resource that collects in the upper areas of the saltmarsh. It is a deadly component of their nests that easily entangles them. Do your part and pick up litter if you see it. © Ben Wurst

Ospreys use trash as nesting material because (sadly) it is a plentiful resource that collects in the upper areas of the saltmarsh. It is a deadly component of their nests that easily entangles them. Do your part and pick up litter if you see it. © Ben Wurst

A few years ago, CWF’s Habitat Program Manager Ben Wurst and his dedicated group of volunteers who monitor the osprey nests along the coast began to hold onto the trash and debris collected in and around the nests. While it may not be the most visually appealing educational resource, it made the growing problem of plastic pollution personal for Ben, in a way that words aren’t always able to convey.

Plastic bags, one of the most common single-use plastic products, were overwhelmingly prevalent in many of the nests. And osprey aren’t the only wildlife species facing this threat. Seals, terrapins, shorebirds, fish, whales, sharks and dolphins can also be impacted by plastic debris.

The presence of plastic in our daily lives is interminable and difficult to eliminate completely, but there are a number of things we can do to minimize the impact our habits may have on our wildlife!

Clean up after yourself:
Whether you’re spending the day at the beach, having a picnic by a lake, or tubing down a river, make sure you take any trash with you before leaving and recycle what you can.

Be mindful of your surroundings:
If you’re out and about and notice that someone left some trash behind, take a moment to throw it away.

Reduce your consumption:
A number of small changes from millions of people can make a big difference. For starters, invest in reusable shopping bags and water bottles. And cut down on the number of miscellaneous throw away plastics you use, including straws and plastic wrappers.

Consider donating to CWF to support our conservation projects and ensure our biologists and our volunteers are able to continue surveying and aiding species in need.



Shark & Ray Conservation Week (Part 6 of a 6-part series – the White Shark)

Friday, July 1st, 2016

This story marks the final of six blog stories spotlighting New Jersey’s shark species.


By Michael Davenport, Wildlife Biologist & GIS Manager

The New Jersey shark attacks of 1916, during which four people were attacked and killed and one injured along the New Jersey shore by one or more sharks, are usually blamed on the great white shark. The great white is definitely a dangerous shark and has been responsible for more fatal shark attacks on people than any other species. However, since one of the attacks occurred upstream within the Matawan Creek, another species (the bull shark) has recently received some scrutiny as being, if not the culprit in all the attacks, at least responsible for some. The bull shark, unlike the great white, is known for frequently entering freshwater, traveling far upstream in some rivers.

A white shark. Photo by Elias Levy.

A white shark. Photo by Elias Levy.

However, Matawan Creek is actually a saltwater tidal creek and is certainly deep enough for a white shark. Eyewitness accounts of individuals who witnessed a shark within the creek in 1916 also describe a shark which is more similar to a white rather than a bull shark. The white shark (either multiple individuals or one shark) remains the chief suspect for at least some, if not all, of the 1916 attacks.

Regardless of whether this is the species which terrorized the East Coast during the summer of 1916, this can be a deadly species due to their size, power, and sharp serrated teeth. This species specializes in preying on large marine mammals, primarily seals and sea lions. Even a “nibble” or “taste” can be fatal to a human.

To learn more about this shark species which occurs in New Jersey waters, visit our Field Guide page.

A bull shark. Was this the real culprit behind the 1916 attacks? Photo by Dana T. Parsells.

A bull shark. Was this the real culprit behind the 1916 attacks? Photo by Dana T. Parsells.