I think there are a couple of birds endemic to Martha’s Vineyard – Colibri or a dedicated birder could be more useful on this. There’s a strain of blueberry plant that’s endemic to a part of Maine – not a distinct species, I don’t think, but a discernable variety or subspecies that is obviously different.
Thanks, I knew you folks would come through. The New England Cottontail caught my son’s interest in particular…who knew (other than Kimstu, perhaps) that we had our own bunnies?
I suspect you are thinking of the Heath Hen, a now-extinct subspecies of the Greater Prairie Chicken that was found in coastal areas of the northeastern US. It was wiped out mainly by over-hunting. The last survivors were on Martha’s Vineyard, where they died out in 1928.
There aren’t any birds endemic to New England. The closest may be Bicknell’s Thrush, which also occurs in eastern Canada and in New York.
Another near-endemic of New England (it was also found in maritime Canada) was the Sea Mink, but that became extinct in the nineteenth century.
There aren’t too many New England endemics, due to the fact that the region was under several thousand feet of ice not that long ago in geological time.
You’re right; I was thinking of the Heath Hen (which had something like a 40 year span as a Martha’s Vineyard endemic) and confusing it with other endemic bird species and subspecies I’d read about in the past.
Though one has to note the irony of the Puritans fighting the heathens and their descendants killing off the heath hens. 
What about Puffins? How far south do they go?
The Atlantic Puffin is very widespread in the North Atlantic, including northern Europe (south to France), Iceland, Greenland, and Canada. The breeding range just barely reaches the US, on a few small islands off Maine.
I’m aware of that, I thought it would fit the criteria of the OP’s situation, which only refers to the U.S. I just wasn’t aware of the extent of the habitat of the bird.
We haven’t done the Naturalist Badge yet, but my suggestion for our kids if/when we do it will be the Barton Springs Salamander. This species is native only to Barton Springs (a swimming hole in Austin, Texas) and to a few other springs in the same park. Concern for the water quality at Barton Springs and for the salamander’s survival has had a major impact on development in the Southwest part of the county.
As worded, I guess it could. Depends on how you interpret “only.”
I agree, and wasn’t meaning to be nitpicky. I was thinking of my own state, Colorado, and some of the birds that live only in alpine climates like the ptarmigan. It exists in NM, WY, MT, OR, WA, and AK, and maybe some others, but it is definitely a localised species.
Come to Florida, we have tons of endemic species. Start with more than a dozen orchid species, move on through insects like Miami Blue and Schaus’ Swallowtail butterflies, up to reptiles like the Eastern Indigo snake, birds including several Seaside Sparrows, and go for gold with mammals like the Key Largo Wood Rat.
This kind of endemism is more common in tropical areas and on islands. There are many endemics especially in montane areas in the tropics.
Saguaro cactus - deserts of Arizona and Northern Mexico
Coast Redwood - coastal (redwood) forests of California and Oregon
Giant Sequoia - Sierra Nevada in California
Excuse the lack of etiquette in reply; due to my web ineptness I keep losing what I’ve typed and having to re-type it and I’m getting bored.
I thought the ivory billed woodpecker was considered extinct.
To simplify the answer inordinately, the Ivory-billed Woodpecker was a relatively reclusive bird despite its size (somewhat larger than the Pileated, and therefore the largest American woodpecker), and favored old-growth forests, which were repidly logged off in the late 1800s and early 1900s. By the late 1930s the only breeding popuation known to survive was in the Singer Tract in rural Louisiana, owned by the Singer Sewing Machine Co. but with logging rights held by the Chicago Mill and Lumber Co. The latter logged the Singer Tract heavily, and by the end of World War II it was believed the IBW had been driven extinct.
Despite this, there were occasional sightings, which could not be confirmed on later searches and were largely though to be sightings of the Pileated, and ‘sightings’ (hearings?) of the IBW’s distinct call, which is quite distinct from any other woodpecker’s. These were largely in Florida, Louisiana, Arkansas, and Cuba.
Investigations into these continued, and in 2004, sufficient evidence had been adduced to suggest strongly that a surviving population existed in Arkansas, with somewhat lesser evidence for a population in rural Florida.
As of this point, the absolute proof needed to say definitively that the IBW has survived is not extant, but the weight of the available evidence suggests strongly that it has.
Extending the “your area of the country” bit a little (but still probably too much to be comfortable), it’s my understanding that lilacs grow only in more northerly climes. IIRC, it’s a cold-adapted plant and requires the environment to get cold enough to put it in a sort of stasis before it can bloom again. It won’t grow (or bloom) properly in southern climates where it doesn’t get cold enough.