Biodiversity gains and losses | Gloucester County Nature Club


Britain has lost half of its plant and animal species in the past 500 years. Most of them were invertebrates and non-vascular plants.

It got me thinking. Excluding these groups, what would early European settlers in New Jersey have seen that they would not see today? A much greater abundance of animals and plants of course, but which species? And would they see something today that wasn’t there then?

They could have seen 54 native species of land mammals. Today, they would find 48, including the coyote which is a relatively recent arrival from the west. Moose, cougars, and wolves are locally extinct, along with the less obvious and poorly documented hairy-tailed mole, fox squirrel, ermine, and New England rabbit.

Of the remaining species, the bobcat, Indiana fruit bat, and eastern wood rat are on the state’s endangered species list. In addition to the coyote, the non-native brown rat and house mouse have been added to our list.

And the birds? It’s harder to define. Over 450 bird species have been recorded in New Jersey, and about 300 occur regularly. Some birds that were once common in New Jersey are now rare and vice versa, but only the Labrador duck, Eskimo curlew, Carolina parakeet, passenger pigeon, and heather hen are globally extinct.

Twenty bird species are on the national endangered species list. Some of them used to breed regularly in New Jersey, but no longer do. Starlings, house sparrows, pigeons, pheasants and house finches are additions.

Settlers could have seen 22 species of snakes, three lizards, and 11 species of land or freshwater turtles. Only one local snake, the semiaquatic crayfish-eating queen snake, is now extinct in New Jersey. The corn snake is endangered.

We still have all the native lizards and turtles, but the bog turtle is endangered. Two non-native turtles, the red-eared slider and the eastern spiny softshell, have established populations in New Jersey, and there are reports of the Italian wall lizard in Burlington County.

Eighteen salamanders and 17 frogs and toads are native to New Jersey. They are all still present, although for many of them their populations are greatly reduced due to habitat loss.

Blue-spotted and eastern tiger salamanders are endangered in New Jersey, as is Cope’s gray tree frog. The green tree frog, a southern species, was recently discovered in New Jersey and appears to have become established there.

And what about plants? There were at least 1,900 species growing in New Jersey when the first Europeans arrived. Of these, 130 are now known to be locally extinct or probably extinct, leaving about 1,770 to be seen. Of these, 291 are endangered.

Some of these endangered plants are rare globally, but most are less so nationally. But nearly 900 non-native plants have become established in the state, making a total of about 2,800 species present today.

For more information on the Gloucester County Nature Club, see


Comments are closed.