1 HACKENSACK, N.J. - Though they have 'rat' in their name, the Allegheny woodrats are nothing like the common rats that skitter across subway rails and leap out of urban dumpsters.
2 Instead, these native New Jerseyans prefer the quiet life outside of cities and look more like jolly, oversized field mice.
3 But times are tough for woodrats. Once common from New England to Alabama, the woodrat has disappeared from Massachusetts, Connecticut and New York, has significantly declined in Pennsylvania, and is nearly gone from Ohio and Indiana.
4 In New Jersey, the only remaining woodrat colony lives in suburban isolation at the foot of the Palisades in Bergen County.
5 The colony has been so cut off from other woodrat populations that their inbreeding has affected the gene pool, making them less able to fight off disease.
6 'Because of roads and development, there no longer is any way for this group to have genetic exchange, and so inbreeding causes the colony's genetic variability to decline,' said Mick Valent, principal zoologist with the state Department of Environmental Protection.
7 He is on a mission to help save the woodrats of the Palisades by trying to keep the colony healthy and possibly importing woodrats from other regions.
8 Humans and raccoons have unwittingly collaborated in the woodrat's decline.
9 Roads and other development have cut off the pathways between woodrat habitats.
10 At the same time, the woodrats have frequent contact with raccoons, which carry a type of roundworm that is often fatal to woodrats.
11 In Bergen County, raccoons are thriving while the woodrats suffer.
12 'Raccoons are far more prevalent today than in the past - where there are people, there are raccoons,' said Valent.
13 That goes for parkland such as the Palisades, where garbage from picnickers is an easy food source.
14 The woodrat's own quirky behavior hasn't helped.
15 Allegheny woodrats exhibit the tendencies of other species collectively called pack rats - they collect shiny objects and bring them back to their nests for no apparent reason - from spent shotgun shells to soda cans, feathers and bones.
16 They also collect dried raccoon droppings, which contain undigested seeds and berries that the woodrat can feed on.
17 Those raccoon droppings often also include roundworm eggs.
18 'The eggs can last practically forever - they are highly stable,' Valent said.
19 'The woodrats ingest the egg and the larvae gets into their bloodstream and the organs and if it hits the central nervous system, it can cause death'.
20 To help stave off the demise of Bergen's woodrats, Valent has launched a two-pronged strategy.
21 Twice a year, in spring and fall, Valent travels by boat along the Hudson and lands at the hard-to-access areas at the base of the Palisades where woodrats live.
22 There, he sets out bait for raccoons, laced with dewormer.
23 The bait includes fishmeal and marshmallow fluff.
24 'They love anything sweet,' Valent said.
25 But it's a challenging battle. 'I see field mice that are infected with roundworm - you can tell because they just walk in a circle,' Valent said.
26 'Then if a raccoon eats the mouse, he's reinfected and it starts all over again'.
27 Valent's other strategy includes a plan to import woodrats from other states to help the Bergen colony's gene pool grow more robust.
28 Woodrats tend to live in boulder fields at the base of mountains and cliffs - providing nooks and crannies to hide from predators.
29 Other New Jersey colonies once lived on Green Pond Mountain and the Picatinny Arsenal in Morris County, as well as the Kittatinny Mountain Ridge in northwestern New Jersey.
30 But they have disappeared. The idea of transferring woodrats from one state to another is not unprecedented.
31 In 2007, Olin Rhodes, a forestry and natural resources professor at Purdue University, collected 54 woodrats from genetically diverse colonies in Kentucky and Tennessee and successfully released them in Indiana, to re-establish populations at four sites that had historically been home to woodrats, as well as to supplement reduced populations at two other sites.
32 Rhodes' team also distributed bait to deworm the local raccoon populations in those areas.
33 Raccoon roundworm is not the only threat to woodrats.
34 In Pennsylvania, there had been colonies in the Lehigh Gorge and the Delaware Water Gap, but the species has largely disappeared east of the Susquehanna River since the end of the 1990s, said Jerry Hassinger, a retired wildlife biologist with the Pennsylvania Game Commission.
35 The species had been in slow decline for a century.
36 The initial hit came in the early 1900s when a fungus laid waste to the American chestnut, which had been the woodrat's main food source.
37 The woodrats could store the nuts through the winter and get a head start on spring reproduction, having up to four litters a year.
38 With chestnuts no longer abundant, woodrats started to rely on oak trees, but oaks are less reliable, tending toward boom and bust cycles of acorn production.
39 And in the 1970s the gypsy moth infestation killed off or weakened many oaks, especially on the rocky Pennsylvania ridge tops where woodrats lived.
40 Human development has chopped up forested regions, creating more 'edge' habitat that favors such woodrat predators as the great horned owl, Hassinger said.
41 Other predators have also grown more prevalent, including black rat snakes and bobcats.
42 Hassinger developed a particular protective affinity for the woodrat.
43 He even took umbrage to that 'rat' moniker, and wrote a poem to that effect.
44 'It ain't wood and it ain't rat,' the poem reads.
45 'These misnomers are a bummer - not funny; we call it the boulder bunny'.
46 Whatever they should be called, the DEP's Valent will continue his efforts to protect the last remaining woodrat colony in New Jersey.
47 If he succeeds, Bergen's 'boulder bunnies' will remain a fixture amid the rubble at the base of the Palisades.

The colony has been so cut off from other woodrat populations that their inbreeding has affected the gene pool , making them less able to fight off disease .
inbreeding
why are they inbreeding?