CottontailNew England’s © ANNE BROWN PHOTO Relict, opportunistic or soon-to-be endangered species, the New England cottontail has managed to keep a low profile. But it is in danger of disappearing from the woodlands of New Hampshire.

BY JOHN A. LITVAITIS

t one time or another, most of us have encountered a small state: Eastern and New England. And it is the New England Abrown bunny while out for a walk or while doing chores in cottontail that has our concern. Before I summarize the reasons for the backyard. If you’re a hunter, your experiences also may have that concern, let me give you a little background information. included walking through a brushy field hoping to kick up a In general appearance, New England cottontails are like rabbit or two for the stewpot. other North American rabbits. Smaller than Eastern cottontails, Hunters and naturalists in New Hampshire know that rabbits New England cottontails weigh just about 2 pounds. Brown and (cottontails) and snowshoe hares both occur in the state. In summer, a conspicuous white tail describe most rabbits. However, if you they’re often difficult to tell apart because they both have a brown look closely, you can find a few characteristics that can help you coat and usually don’t stand still long enough for us to get a good distinguish a New England from an Eastern cottontail. About look. In winter, however, the coat of a snowshoe hare turns white half of Eastern cottontails have a small white spot on their and that of a cottontail remains brown. But you may be surprised forehead. This is never found on a New England cottontail. The to know that we actually have two species of cottontails in the ears of a New England cottontail are shorter than those of an Eastern and there is a thin black line of fur along the outer edge. John Litvaitis is a professor of wildlife at the University of If you look closer, you’ll also notice a black spot right between New Hampshire and has authored many papers on wildlife the ears of a New England cottontail. These are the only ecology in professional publications. differences you can see.

W7ILDLIFE J OURNAL WILDLIFE J OURNAL 7 If you’re a hunter, you know that Eastern are well known. During the late 1960s and early You have to look cottontails will often take you and your dog on a 1970s, Bob McDowell and a group of his students carefully to distinguish good run. But if you’ve ever encountered a New at the University of Connecticut searched for an an Eastern cottontail England cottontail, you know that they quickly answer to this question. McDowell and his stu- (top) from a New dart into an underground den or a rock wall as soon dents suggested that the early-successional habi- England cottontail as they sense danger. Perhaps the most important tats preferred by New England cottontails were (bottom). About half of difference between the two rabbits is where you’ll being lost to development and forest maturation. the Easterns have a find them. Eastern cottontails are found anywhere Additionally, New England cottontails were small white spot on there is a grassy opening and some nearby cover. apparently being displaced by expanding popu- their forehead; New A suburban lawn (food) and hedge (cover) can be lations of the larger (and assumed dominant) East- Englands don’t have ern cottontail. During the 1920s through the 1950s, suitable habitat for an Eastern cottontail. But this. The eyes of the state wildlife agencies and private hunting clubs you’ll never find a New England cottontail in Easterns are also these areas; they require very dense cover and introduced thousands of Eastern cottontails into bigger than New rarely venture far from it. southern New England. Most of these rabbits were Englands. And the ears Among the three species of rabbits and hares from populations in Kansas, Missouri and Texas. of a New England are found in New Hampshire and most of New En- Prior to these releases, Eastern cottontails ranged gland, a great deal is known about Eastern cotton- only as far north as southwestern Connecticut. shorter, with a thin tails and snowshoe hares. However, only limited These introductions probably triggered the ex- black line along the research has been directed toward understanding pansion of Eastern cottontails to areas as far north outer edge. A New the ecology of New England cottontails. This as the Canada-Vermont border. The notion that England also has a rather nondescript rabbit managed to evade tax- expanding populations of Eastern cottontails was black spot between the onomists for nearly a century. It wasn’t until 1895 affecting New England cottontails was quite ap- ears. that Outram Bangs first described New England pealing because the expansion cottontails as a subspecies of Eastern cottontails. of Eastern cottontails roughly Fourteen years later, E. W. Nelson recognized that coincided with the decline of this rabbit was indeed a distinct species. New England cottontails. But What really surprised biologists was a report in evidence was lacking. 1992 that indicated the New England cottontail Since 1990, I have been was actually two species! Based on regional dif- working with a group of gradu- ferences in chromosome numbers, populations ate students at the University west of the Hudson River in New York are now of New Hampshire to deter- considered “Appalachian cottontails,” whereas mine if this explanation or those to the east retain the name “New England others could help resolve why cottontail.” Most of us are only mildly surprised an animal like a cottontail to hear that a new species of bird or insect has been could be threatened with ex- encountered in the rain forests of South America. tinction. I suspected that habi- After all, taxonomists have only recently entered tat change was a more likely those forests. But to discover a new species of explanation for the decline in mammal in one of the most densely populated New England cottontails than regions of North America was quite unexpected. competition because there are

regions of New England (es- © ALAN BRIERE PHOTO Threatened with Extinction pecially central New Hamp- shire and southern Maine) The revision in taxonomy may have some where Eastern cottontails do unexpected consequences. Wildlife biologists not occur and populations of have known that the abundance of New England New England cottontails have cottontails has declined sharply since the early still declined. 1960s. In spite of this decline, no serious action To appreciate the role of was taken, apparently because populations in the habitat change on New En- southern Appalachians seemed quite secure. How- gland cottontails, a short re- ever, these populations in the South are now view of the history of land use known to be Appalachian cottontails. As a result, in New England is helpful. In the New England cottontail may have the dubious New Hampshire, for example, distinction of becoming the newest threatened or relatively continuous forests endangered species in the United States because covered approximately 90 its range has declined by more than 75 percent. percent of the state at the time What could have caused such a rapid decline of settlement by Europeans. for a species like the New England cottontail? Like most colonized regions, After all, the reproductive capabilities of rabbits continued on next page

W8ILDLIFE J OURNAL WILDLIFE J OURNAL 8 RANGE OF THE NEW ENGLAND COTTONTAIL From 1900 through 1960, there was an accumulation of Circa 1960 Current Range young forests throughout New England, filled with the thicket habitat ME ME preferred by the New England cottontail. After the early 1960s, these young forests VT VT began to mature. The NH NH New England NY NY cottontail is now found in only a few MA MA scattered places in its namesake range. CT CT RI RI

forests were cleared for agriculture, and by 1880 To investigate this scenario, my students and remnant forests covered less than 40 percent of the I constructed a large enclosure where we placed state. But agriculture did not persist. Farmers both species. Rabbits adjusted quickly to the could not produce large enough crops from the enclosure. The only detectable difference be- thin, rocky soils to compete with midwestern tween them was that Eastern cottontails were agriculture. Most of this land was left idle and often observed in areas with little understory reverted to second-growth forests. cover. We then placed one of each species into a Using this information and a simple model of smaller enclosure to make more detailed observa- forest growth, I estimated that there was an accu- tions. To our surprise, Eastern cottontails did not mulation of young forests throughout New En- have an obvious ability to overpower New En- gland from approximately 1900 to 1960. Such gland cottontails. When rabbits were involved in During the 1920s forests were ideal for New England cottontails and “disagreements,” New England cottontails won through the other animals that rely on “thicket habitats.” about half of the bouts when there was a clear 1950s, state However, by the early 1960s, these lands matured winner. Physical domination, therefore, did not wildlife agencies into closed-canopy forests that were no longer explain why Eastern cottontails were more suc- suitable for rabbits and their populations rapidly cessful. and private declined. This pattern of land clearing and forest Our next experiment was a bit more elaborate. hunting clubs growth also explains the rise and fall of other We constructed a second enclosure where we were introduced mammals and birds that are dependent on young able to separate rabbits in individual sections of thousands of forest habitats, including bobcats, ruffed grouse the enclosure. Next, we built special feeders that and woodcock. would enable us to remotely monitor rabbit activ- Eastern cottontails ity. Each feeder was equipped with an electronic into southern New Battle of the Bunnies sensor that recorded when a rabbit was present. A England. series of experiments was conducted to under- Our ability to understand the rapid decline in stand how both species used an environment populations of New England cottontails was ex- where they had to choose between food and cover. plained by the loss of young forests. But one issue In one series, it was clear that Eastern cottontails was still puzzling. How could Eastern cottontails would venture away from cover to get enough to expand their range while populations of New eat. Our farthest feeder was about 60 feet from England cottontails declined? Previously, biolo- cover, a long distance for a rabbit trying to avoid gists speculated that the larger Eastern cottontail a hungry fox or owl. New England cottontails (about 3 pounds) physically dominated the smaller were very reluctant to visit these feeders unless New England cottontail (about 2 pounds). This they started to lose weight and were clearly very physical dominance suggests that as populations hungry. of Eastern cottontails expanded throughout south- We extended the experiment for about two ern and central New England, they simply replaced months and had some very interesting results. endemic populations of New England cottontails. Although we had constructed the enclosure to

W9ILDLIFE J OURNAL WILDLIFE J OURNAL 9 keep predators out (6-foot chain-link fence with nylon lines strung over the top), a couple of owls managed to periodically catch a rabbit. Over the course of the extended trial, twice as many New England cottontails were taken by the owls in comparison to Eastern cottontails. For some rea- son, New England cottontails seemed to be more vulnerable to predators. Perhaps this could ex- plain the differences in their respective responses to land use change. In an earlier field study, we found that popula- tions of red foxes and coyotes in southern New Hampshire increased as land-use patterns shifted from forest dominated to a mix of forest, farmland and suburban developments. Such diverse land- scapes describe much of New England. Both of these predators are quite adaptable and they seem to benefit from the additional food sources asso- ciated with farmlands (more rodents) and devel- opments (trash). Red foxes and coyotes also were the most common cause of death of the 75 radio- Here again, we were quite surprised by the A New England tagged New England cottontails we monitored results. Eastern cottontails detected the approach- cottontail is placed throughout southern New Hampshire. But why ing owl when it was about 70 feet away. Clearly in a wire cage would one rabbit be more vulnerable to preda- this detection distance would often let the rabbit (above) as part of an tors? After all, they look almost identical – or do escape to cover. New England cottontails, on the experiment designed they? other hand, did not respond until the owl was only to determine if the 30 feet away. These results indicate that New Eastern cottontails Watch Out for That Owl England cottontails may be more vulnerable to can detect an predators when they are in open habitats. Our final experiment approaching But what adaptations predator at greater was an effort to under- do Eastern cottontails distances than the stand if Eastern cotton- have that are apparently New England tails could indeed detect lacking in New England cottontails. an approaching predator cottontails? Quite simply, sooner and at greater dis- big eyes. We found that tances than New England © ALAN BRIERE PHOTO the eyes of Eastern cot- cottontails. If they could, tontails are about 50 per- then this would explain cent bigger than those of their ability to occupy a New England cottontails. variety of habitat includ- As a result, they are prob- ing those with limited ably taking in a much cover. To investigate larger area and thus able this, we took a low-tech to spot a predator sooner approach. We con- (and further) than a New structed an owl using a England cottontail. This plastic model and added difference is probably a some plywood wings that consequence of the origi- The Eastern cottontail, with its big eyes, we painted black. Next, nal habitat that each rab- we built a wire glide that can better detect a predator (such as an bit occupied. Eastern cot- enabled us to hang the owl) than a New England cottontail. tontails likely evolved in owl model on a pulley large open habitats of the and sail it along the wire. To examine the response Midwest. New England cottontails are essentially of each rabbit, we placed individuals in some wire a woodland species, probably most abundant in cages and positioned a nearby video camera to native shrublands (especially mountain laurel focus on the rabbit. Next, we marked the wire with and scrub oak) or young forests created by fires, distances from the rabbit’s cage and attached a hurricanes and beaver flowages. A woodland spe- microphone to the video camera that let one of us cies would not have an opportunity to detect a speak onto the tape while tracking the owl and predator at long distances, and so did not evolve recording the rabbit’s reaction. continued on next page

10WILDLIFE J OURNAL WILDLIFE J OURNAL 10 bigger eyes. Because staying close to cover is provide a complete picture on the status of New probably the best strategy in forest habitats, New England cottontails. Although England cottontails suffer disproportionately We have completed most of our survey of New managing thicket when cover shrinks. Recent landscape modifica- Hampshire, and our results indicate that the New habitats doesn’t tions, especially suburbanization, continue to England cottontail isn’t faring very well in the state. generate the reduce the availability of habitats required by Populations occur in Strafford County, including New England cottontails. Roads and develop- the towns of Barrington, Dover, Durham, Lee and public enthusiasm ments also have fragmented and isolated what Rollinsford. Here, cottontails occur among a variety as some other habitat patches are present. Such habitats are still of habitats, especially former agricultural lands that programs have, adequate for Eastern cottontails. have been idle for 10 years or more. These sites are it’s important to dominated by thick shrubs and young trees. Finding New England Cottontails Unfortunately, many of these sites are “just remember that a waiting” to be developed. A standing joke I have variety of habitats Will the New England cottontail survive? with graduate students that are trying to capture are needed by Unlike many other rare or endangered species, the cottontails for their individual projects is to set habitat of New England cottontails is relatively wildlife. box traps wherever they find a “Land for Sale” easy to maintain. Perhaps it isn’t too late to take sign. Many of the areas where we studied cotton- steps to ensure that this species doesn’t vanish tails in the mid 1990s are now developed into from our forests. The first step of any restoration suburban neighborhoods and it seems likely that plan is to have a good understanding of what you more of the habitats currently occupied by cotton- have. tails will be developed. Last year, I began collaborating with state and federal wildlife biologists to get a more complete picture of New England cottontails in New Hamp- Threatened Thickets shire and the rest of New England and Eastern New The other region where we have found New York. For two years we will inventory the entire England cottontails is the Merrimack River cor- region to identify places that still support cotton- ridor, including the towns of Bow, Hooksett, tails and vacant habitats that could support them Derry, Windham and Londonderry. Additionally, if they were transplanted there. Of course we won’t cottontails are still hanging on in Manchester, be able to visit every patch, but we will search sites Litchfield, Bedford, Merrimack and Hudson. throughout the state. Development activity in this region is probably The New England’s Additionally, we are using a new approach to the most intense in the state and we were surprised habitat is a thicket, a find rabbits. Rather than setting box traps baited to find rabbits here. Most occupied patches of messy tangle where it with apples, a method that is effective but takes a habitat are small, usually a few acres or less. has cover and food. great deal of effort, we will search patches for Industrial parks seem to be especially popular In New Hampshire, rabbit pellets. For several years, I have been work- among cottontails. But as development of these this type of habitat ing with molecular biologists to develop a tech- areas continues, cottontails will be squeezed out. has been reduced to nique that would enable us to identify rabbits Based on historic observations by biologists small patches from their fecal pellets. As digested food passes affiliated with New Hampshire Fish and Game, we (usually a few acres, through a rabbit’s intestines, a few cells from the anticipated encountering New England cotton- more or less). intestine are scraped away and are embedded in tails in the Connecticut River Valley, especially their pellets. Our technique recovers the DNA in in the area of Keene, Westmoreland and Walpole. the pellets and al- But we only found Eastern cottontails in this lows us to deter- region this past winter and are left to conclude that mine what species New England cottontails may have been extir- provided the pated from the Connecticut River Valley. sample. Field tri- Once the range-wide inventory is complete, als last winter were biologists can use the information to develop a very encouraging: comprehensive management plan. Efforts to aid From 141 samples New England cottontails also will benefit other collected mostly thicket species. Although managing thicket habi- in New Hamp- tats doesn’t generate the public enthusiasm as shire, we were able some other programs have, it’s important to re- to identify the member that a variety of habitats are needed by source of 132 wildlife. Shrublands and early-successional for- samples. This ests are important breeding, feeding and cover technique should habitats for a large number of species. So let’s enable us to cover make sure these habitats are available for our own a large area and New England cottontail. PAUL FUSCO PHOTO © CONN. DEP

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