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Posts categorized New Jersey Preserves.

Turtle on the federal endangered species list, but not here

By Steve Eisenhauer, Regional Director

The red-bellied turtle is a threatened species in Pennsylvania but in New Jersey it is quite common. Each spring at our Harold N. Peek Preserve we see these dime-sized babies making their way to the water. Although the majority of these hatchlings are believed to hatch and emerge from the ground in late summer, some overwinter in the nest chamber and emerge the following spring. Here is one of a few that were found on April 1.

The red-bellied turtle (Pseudemys rubriventris) is the most commonly seen turtle at Natural Lands Trust’s Peek Preserve, mostly due to its large size (up to a foot long and 10 pounds as adults), its tendency to sun itself on logs, and its springtime overland trips to lay eggs. Central New Jersey is the northernmost range of this species, with one exception being a population 250 miles away in one Massachusetts county. This Massachusetts population numbers in the hundreds, and merits federal endangered species protection. Many scientists believe that, perhaps hundreds of years ago, the two populations were connected, but habitat changes and collectors (primarily for food and pets) created the gap between the two populations. In Pennsylvania, this turtle is found only in the state’s southeastern corner, and is listed as a state-threatened species.

Evidence of turtle nests is found at the Peek Preserve, particularly in late summer and fall in areas within 100 yards of the Maurice River. Many are red-bellied turtle nests, but box, musk, mud, red-ear, and painted turtles also lay eggs in the area. Torn above-ground eggshells indicate a predator (most likely a fox, raccoon, or skunk) has made a meal of the eggs by digging them out. Turtles that hatch alive typically leave their eggshells underground, but then have to deal with the many hazards of life in the wild  The dime-sized red-bellied turtle hatchlings are a tasty morsel for many land animals. If they make it to the water, a wealth of hungry fish and bird species (particularly Great Blue Herons) will be waiting for their arrival.

Although most red-bellied turtles hatch and emerge in late summer and fall, some hatch and remain in the nesting chamber until the following spring. It’s always a treat to see them making their way to the water in April, although it’s also humbling to pick them up and help them to their destination: the half-mile wide Maurice River which, in early spring, is essentially devoid of vegetation and other protective cover. It’s surprising any survive at all.

See more photos of these turtles in our slideshow:

Photos by Steve Eisenhauer, staff member.

Crow’s Nest: A little piece on Radio Times

By Daniel Barringer, Preserve Manager

There was a nice plug for the preserve on Friday’s NPR show, Radio Times. It’s a piece entitled, Autumn leaves and heirloom apples, and the first portion features an interview with Susan Charkes, author of Best Day Hikes near Philadelphia and John Brunner, Mid-Atlantic Recreation Planner for the Appalachian Mountain Club (the second part, with Rowan Jacobson, about unusual varieties of heirloom apples, is also quite good).

Susan and I co-led a hike at Crow’s Nest that focused on land stewardship a few weeks ago, and she has also co-edited with Dr. Ann Rhoads Natural Lands Trust’s Stewardship Handbook, now in an updated 2nd edition entitled Land for LifeCrow’s Nest does not appear in her first edition of Best Day Hikes… but she says it will be in the next.

She mentioned Crow’s Nest in the Radio Times piece, and John Brunner went on to mention a couple other Natural Lands Trust preserves as noteworthy places to visit: Mariton Wildlife Sanctuary near Easton, Pennsylvania, and our Glades Wildlife Refuge in Cumberland County, New Jersey.

We appreciate the kind words, and agree—hope to see you at the preserves this fall!

New Jersey: A Time for Warblers

By Brian Johnson, Preserve Manager, and Ariel Senko. Photos by Brian Johnson.

Prothonotary Warbler       Black-and-White Warbler              Prairie Warbler        

This past month, our southern New Jersey preserves have been full of warblers, which are a treat to see in their magnificent breeding plumage. Brian Johnson, New Jersey preserve manager, says that 16 warbler species breed on our southern Jersey preserves and up to 35 species pass through in May, though a few years can pass between sightings of some of the species. The peak season is just about over, but the 16 species that breed on our preserves may be spotted well into the summer.

 Neo-tropical migrants, most of the warblers we see in the U.S. winter in Central or Southern America. (Some are satisfied with wintering in southern Florida.)  The three varieties pictured here are the Prothonotary Warbler, the Black and White Warbler, and the Prairie Warbler, respectively. As you may notice, the predominant color among warblers is yellow, though they may also sport blues, oranges, reds, greens, greys, black, and white. All warblers consume insects and spiders; a few species have more diverse diets, and will eat berries, seeds, and nuts.

Most warbler species prefer to spend their time high in the trees (the better to catch flying bugs), so experienced birders will often rely on warblers’ songs to help them identify the birds. There is a reason that the aches that birders sometimes experience from staring up for extended periods of time is called “Warbler Neck”—the warblers are so pretty that birders can’t help themselves!  

The Prothonotary Warbler

Prothonotary Warbler

The Prothonotary Warbler is known as the only cavity-nesting Warbler on the East Coast, preferring old woodpecker holes and hollowed trees. Of the three warbler varieties pictured, only the Prothonotary population entirely leaves the U.S. for the winter. Since so many warblers are yellow, it can be tricky to tell them apart at first, but if you see a yellow bird with a full blue/gray wing on our preserves, you can be sure that it’s a Prothonotary. The only other warblers with so much blue on their wings are, well, Blue-Winged Warblers, which have a black band across their eye and aren’t common on this part of the East Coast.


The Black and White Warbler

Black-and-White Warbler

The Black and White Warbler goes up and down the lengths of tree trunks to hunt for insects on and underneath the bark, much like a Nuthatch or Brown Creeper. These Warblers seem to prefer broadleaf or mixed uplands. Despite spending so much time feeding in trees, Black and Whites prefer to nest on the ground. Their plumage is striking, but their stripes actually help them to blend in with their surroundings, making them easy to miss.


The Prairie Warbler

Prairie Warbler

Prairie Warblers breed in early successional habitats—overgrown fields with sparse, young trees, and prefer to nest in shrubs or trees no more than 10 feet off the ground. Some fun facts about these Warblers—they will sometimes hang upside down on a branch to eat bugs on the undersides of leaves, and are also know to eat the eggshells of their young as soon as the young have hatched.


All three of these Warbler species are rated by the International Union for Conservation of Nature (ICUN) as a species of “Least Concern,” but bird-watching organizations around the country including the National Wildlife Service agree that many Warbler populations, as well as those of many other neo-tropical bird species, are currently declining. Other populations appear to be stable but have concentrated populations, and they may be at risk if those habitats are altered or lost.

Of the three Warblers featured here, the Black-and-White Warbler is doing the best, thanks to its relatively extensive breeding and wintering ranges (from southern Canada through Mexico and Central America into the northwest coast of South America), and the variety of habitats it will tolerate.

Prothonotary Warblers like to live in tree cavities above standing water, which is why they like New Jersey—for the swamps and wetlands. Prothonotaries prefer to nest in larger tracts of forest and are believed to be suffering a loss of habitat due to development and deforestation. The installation of nesting boxes (as substitutes for tree cavities) and efforts to restore bottomland forests along the Mississippi River have led to increased populations in the U.S., but the birds still face loss of habitat in their wintering grounds south of the U.S.

Prairie Warblers, on the other hand, prefer fields with small trees and shrubs. They actually lose habitat as forests naturally mature. The good news is, Natural Lands Trust’s stewardship staff use a stewardship technique that periodically eliminates the young growth of new trees that would result in the gradual loss of the Prairie Warbler’s preferred habitat in certain parts of our preserves—controlled burns. Prairie Warblers, like Prothonotary Warblers, still face loss of habitat in their wintering grounds outside the U.S.

In addition to loss of habitat, many Warblers are also susceptible to pesticides that are used in communities to kill mosquitoes, and parasitism by the Brown-headed Cowbird, which, making no nest of its own, will lay its eggs in Warbler nests. The Cowbird brood, which are usually larger than the Warbler brood, become competition for food from the Warbler parents, and may even remove Warbler eggs and young from the nest. Cowbirds prefer to live in open land near trees, but not in forests, so deforestation has exacerbated the Cowbird parasitism problem. 

The main threat to Warblers, however, continues to be loss of habitat in their wintering grounds. Since Congress passed the Neotropical Migratory Bird Conservation Act (NMBCA) in 2002 in order to promote the long-term conservation of neotropical migratory birds and their habitats, millions of dollars have been raised every year to fund collaborative conservation projects in North, Central and South America. This year, $12.5 million was raised to protect more than 250,000 acres of this critical habitat, including pine-oak forests of Central America, critical bays in Panama and Paraguay, high Andean wetlands, the Ecuadorian Choco.


A Rare Glimpse of the Seclusive Long-eared Owl

Brian Johnson, a member of our land stewardship staff, considers himself very lucky to have spotted this Long-eared Owl (Asio otus) at one of our New Jersey preserves. Brian said that Long-eared Owls are extremely secretive, and will often take off at the sight of a human, even if that person is far away. Long-eared Owls are less common than Great Horned Owls (Bubo virginianus) and when found are usually in dense evergreen forests.

Brian was able to take this shot from 75 feet away, using a Canon Digital SLR camera with a 400 mm lens. Brian lucked out not only because the owl didn’t fly away once he was in sight, but also because the owl had chosen an unusually low perch in an evergreen tree. They are usually much higher up, making them nearly impossible to spot through layers of branches.

How to tell a Long-eared Owl from a Great Horned Owl?  Brian says both species have prominent ears, but the Long-eared Owl’s ear tufts are closer together, and more centered on the top of its head, while a Great Horned Owl’s ears are more to the side, “like a cat’s ears.” Great Horned Owls are also chunkier than the long and lean Long-eared Owl, as seen in Brian’s photo.  Brian says the owl stretched itself out when it saw him, assuming what is known as a “camouflage posture.” However, it remained in the tree because Brian did not try to approach it too closely.

According to Brian, during some years, a fair number of Long-eared Owl winter in southern New Jersey, sight-unseen. Trees that the owls choose to roost in are often “white-washed” with owl droppings and the ground littered with owl pellets, but, Brian says, by the time you come across such a tree it is almost certain that the owl has left the tree.

Our preserve stewardship staff has observed a fluctuation in owl populations from year to year; it depends on the population of the owls’ prey: mostly meadow voles and rice rats in the tidal brackish areas. During the clean-up process on our New Jersey preserves after Hurricane Sandy (which is still on-going—see other recent posts by our management staff), Brian helped to clear preserve trails of “wrack”: uprooted or dead grasses and other debris carried by water and deposited on the trails. The wrack was full of hundreds of dead rodents that had drowned in the storm waters.

Since Hurricane Sandy, meadow vole and rice rat populations have been relatively low, and are likely to remain low until their usual breeding seasons this spring and summer. Since the New Jersey salt marsh rodents’ populations took such a hit this past fall, Brian says it is likely the owls that usually depend on them for prey may be moving further inland in search of food.

Brian recommends if you do find an owl, don’t approach too closely and crouch down making yourself less threatening. Try not to disturb the owl by returning frequently, and don’t tell anybody where you have found the owl! This way you may be able to enjoy owls roosting in the same spot year after year. If disturbed too frequently owls often abandon a roost site, and may never return again.


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