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Lagomorphs Our Only Native Cottontail Has Been Replaced by a Nearly Identical-Looking Alien, Seemingly Body-Snatched Before

Lagomorphs Our Only Native Cottontail Has Been Replaced by a Nearly Identical-Looking Alien, Seemingly Body-Snatched Before

Our only native cottontail has been replaced by a nearly identical-looking alien, seemingly body-snatched before our eyes in just the last 50 years. The range of our only native is likely to retreat northward beyond our borders in the next 50 years. What do we really know about our vanishing ?

by Peter G. Mirick forest regions with cold winters and deep snow cover, could almost be a It’s hard not to love bunnies. Everybody poster child for the wildlife implications does: , , fisher, , , of climate change. Maybe it’s time we larger and owls, big , house gave our Bay State bunnies a little more , , domestic , and people. attention. Not to mention any number of trema- todes, cestodes, , lice, , Lagomorphs and . Bunnies seem to have evolved Cottontails, which are rabbits, should as the ultimate prey: profusely abundant, not be confused with , which fast reproducing, easily dispatched (once are hares, and since people seem to you catch them), and possessing a satisfy- have a predilection to use the terms ing amount of nutritious . They are interchangeably, and since both can be the daily bread of a thousand predators, lumped under the vernacular bunny, we a broad band in the upper foundational might as well set the record straight. Rab- layer of temperate food chains across the bits and hares are lagomorphs, meaning globe. So popular are they that several they belong to the , have been transplanted inter- which also includes a diverse of continentally, allowing some to become exceptionally cute little furballs called that have significantly (none of which live in , impacted the ecosystems into which they unfortunately, but some of which, be- were introduced. cause they live in isolated alpine Here in the Commonwealth we have or “sky islands” in the form of mountains only two native species, the New England from which they cannot depart alive, cottontail, Sylvilagus transitionalis, and may already be critically endangered the , Lepus americanus. by climate change). Lagomorphs were Neither could be said to be thriving. The once classified as despite their has exhibited an unique dentition (in particular, a set of extreme (> 75%) decline in numbers and rounded “peg teeth” directly behind range over just the past few decades, their upper incisors) and they were not largely replaced on the landscape by the taxonomically emancipated from the rats introduced , Sylvilagus and mice until 1912. They may actually floridanus. Its continued survival appears be more closely related to the to be in imminent jeopardy and it is now a than they are to the rodents. candidate for federal endangered species Rabbits and hares share a number of listing. Meanwhile, the snowshoe hare, obvious characteristics including a high a northern ideally adapted to reproductive rate and long, indepen- 23 Photo © by Bill Byrne Hares are bigger, longer-legged, and just plain tougher and lankier than cottontails. This Snowshoe Hare, in summer coat, also has coarser than a cottontail. dently controlled ears that offer superb and young. This is to be expected in a directional hearing and also function non-social species: they just don’t have as thermal radiators when their owners much need for auditory communication become overheated. They have a cleft that could alert predators to their pres- upper lip that aids them in food manipula- ence. Our lagomorphs do thump their feet tion. Their skeletal structure is evolved when alarmed, however, and thus may to handle the multiple g-force stresses of altruistically alert nearby individuals to fast acceleration and sudden changes in the approach of danger. direction when in full flight. Their hind legs are longer and much stronger than Refection their front legs, and although they will All three of our lagomorphs practice use a digitigrade walking gait, their stan- refection, a sort of “pseudorumination” dard locomotion is a hop. that allows them to extract maximum They tend to be nocturnal, or at least benefit from their food without having crepuscular (active at dawn and dusk), to carry the four stomachs of a and most have excellent vision. Their around with them. They do this with the typically large eyes and narrow , aid of a special food storage/fermentation somewhat reminiscent of the woodcock’s vat of an organ called the cecum, located in design, allow them continual, near- between the small and large intestines. 360° monitoring of their surroundings; The short version goes like this: a very useful ability for that The consumes bark and greenery, could accurately be labeled “universal the stomach churns it up, and the small prey.” When injured or captured, all of intestine absorbs whatever nutrients are our lagomorphs are likely to produce present before squirting it all into the surprisingly loud squeals full of heart large intestine. The large intestine, which rending terror. Otherwise they rarely cannot absorb nutrients, separates the make any noise at all other than some high fiber, low nutrient material from the soft calls exchanged between mothers high nutrient, low fiber material passing 24 Photo © by Bill Byrne More delicate in size, bone structure, and ability to withstand cold and snow, the Eastern Cottontail has a finer, shorter coat than its larger snowshoe cousin. through it. The low nutrient material is than rabbits (although not necessarily packed into hard pellets and deposited as so when served at the table) and they waste, resulting in those familiar batches don’t dig or live in . They are of “rabbit raisins” all outdoors people solitary in their habits and have never readily recognize. The high nutrient ma- been domesticated. They typically feed terial is sent back into the cecum where at night and spend their days quietly bacterial action breaks it down into sug- concealed in thick, overhanging cover or ars, amino acids, and other absorbable in the shadow of a rock ledge or boulder. nutrients. Following fermentation, and No carefully prepared, fur-lined nests for always timed to be deposited during the them. A mother hare (doe) simply picks ’s daily resting period, the cecum a secluded spot, flattens a small area in squirts the wholesome mixture back the vegetation, and gives birth to preco- into the large intestine, which packs it cial young, called leverets, that enter the into special soft, greenish pellets, called world fully furred and with their eyes , and sends them out to be im- open. Leverets can get around when just mediately reingested by the rabbit. The a day old, and if threatened, they rarely nutrients are then absorbed in the small go meekly into that red maw, but growl intestine on the second pass. Thus the and fight for their lives. The doe nurses animal acquires a number of precious them just once a day, during evening nutrients and crucial vitamins that would twilight, and they are fully weaned and otherwise have been lost as waste. It is on their own at 4-5 weeks of age. quite a feat of bioengineering. Rabbits are generally more delicate creatures than hares, rarely reaching In general, hares are larger than rab- weights of 5 pounds. (The biggest in bits, some species reaching weights of is the , S. 10 pounds or more, with longer ears, aquaticus, a semi-aquatic rabbit that fa- longer legs and feet, larger nostrils (for mously attacked President Jimmy Carter rapid air cycling), and lankier bodies built in 1979.) Worldwide, most species live for speed. Hares are just plain tougher in comfortable burrows. The European 25 rabbits that were the main characters their eyes closed. It takes them more than in Richard Adams’ Watership Down two weeks to grow fur, open their eyes (and which were domesticated by the and develop sufficiently to leave the nest, Romans some 3,000 years ago) live in but like hares, they mature very quickly social groups in communal sys- and are weaned and fully independent tems called warrens. Cottontails are an at 4-5 weeks of age. exception among the rabbits in that they follow the minimal burrowing habits and Snowshoe solitary lifestyle of the hares, although Although the , the Eu- they will make occasional use of hollow ropean rabbit, and the black-tailed jack- logs, woodchuck holes, or natural cavi- rabbit were stocked in in ties under stumps and rocks, especially the last century, establishing resident during periods of cold, wet weather. populations in (respectively) Berkshire More often they spend their days in a County, the Boston Harbor Islands, and form, a cup-like “bed” concealed in long on Nantucket Island, these populations grass, weeds, or thick brush that fits the now appear to have failed. The snowshoe animal’s lower contours and insulates it hare was also stocked extensively in the from weather and prying eyes. Cottontail Commonwealth in the last century, most- does dig shallow hollows and line them ly in response to a major decline of the with layers of grass, fecal pellets, and population following the drastic changes their own fur to make a nest. Their young in and land use that occurred in are altricial, born nearly naked and with Photos © by Bill Byrne Typical of all New England lagomorph behavior, these Snowshoe Hares feed in close proximity to cover where they can instantly retreat if a predator (such as the , inset) is detected. The ability to perceive the presence of a predator earlier than the competition is believed to be one of the Eastern Cottontail’s superior survival skills; one of the reasons it has been able to replace the New England Cottontail in all but the most predator-impenetrable habitats. 26 Photo © by Bill Byrne This Snowshow Hare in winter coat displays the oversize hind feet – an for living in snowy, northern regions – that gave the species its common name. the 19th century. Tens of thousands of fingers of distribution that follow the wild-caught, Canadian snowshoes (most Appalachian, Rocky, and Sierra Nevada from New Brunswick) were released by mountain ranges. It gets its name from the Division of Fisheries & Wildlife and its exceptionally large hind feet. These authorized sportsmen’s groups from 1891 feet are heavily furred, even on the soles, through the 1980s. and their four digits can be spread widely Snowshoes are natives, however, and apart. This provides the animal with the stocked animals did little more exceptional predator-escaping footing in than temporarily supplement existing soft snow, allows them to stand on their numbers, providing additional for hind feet in snow to reach overhead food hunters and their dogs just as stocked sources, and leaves a track as distinctive trout provide supplemental game for as Karl Malden’s nose. When in a hurry anglers. While the snowshoe popula- they can cover ground in 8-10-foot jumps tion has certainly declined in range and and hit speeds of 30 mph. numbers – and will likely continue to The snowshoe is also called the “vary- do so as habitat succession, habitat de- ing hare” because its coat changes color struction, and climate change continue twice each year, going from a summer – for now it remains locally common in brown to a winter white and back again. scattered habitats throughout the state These molts take about 10 weeks to except for Dukes and possibly Nantucket complete and take place from October- counties. December and March-May. The autumn The snowshoe hare weighs from 2-5 molt begins on the ears and feet and ends pounds and grows to a length of 15-22 on the back, while the spring molt starts inches, making it a little bigger and on the face and body and ends on the longer than either of our cottontails (14- ears and feet. The timing of these color 18 inches; 2-3 pounds). It ranges from changes is always a gamble: sometimes Alaska to Newfoundland, along most of the snows come early or late, and in Mas- the northern border of the , sachusetts, of course, sometimes there and far southward along higher-elevation is no snow cover at all for periods in the 27 Winter fodder for both Snowshoe Hare and our cottontails consists of bark, buds, and twigs. seedlings in the cold ones. Trappers have noted they sometimes eat meat used to bait traps, so they prob- ably take a few nibbles on carrion, especially bones, if the opportunity presents itself. Most individuals have a home range of 10-25 acres and display daily movements covering around 5 acres, but much depends on the quality of the habitat and the proxim- ity of food sources to the cover of the daytime bed. It is common for individu- als to use the same trails habitually, especially in swamp habitats, produc- ing well-worn paths like those of a porcupine. The preferred habitats where the highest densities of snowshoes occur are low- land conifer forests, young aspen stands, and spruce and cedar swamps, but snowshoes can be found almost anywhere in mixed forest/swamp/old field habitats throughout most middle of winter. While a brown animal Photo © by Bill Byrne of the state. (like either of our cottontails) can stick to Snowshoes breed from March through thickets and shadowy hollows for cover August. Courting may involve violent, and manage to survive our temperate even mortal battles between males. Mat- winters (especially in years when snows ing events are usually preceded by long are light and not long-lasting; they suffer chases, bizarre vertical leaps, and much if winters are long and the snow is deep), jumping over/running under each other, it appears that a white animal on a brown with both sexes urinating on each other forest floor is a high contrast beacon for during the process. (Cottontails do the predators. This means that if the snow same thing; talk about being “mad as a line retreats north as climate change ”!) Females in Massachusetts progresses, it is likely that the range of usually produce 2 to 4 litters per year, the snowshoe will retreat along with it. with litters numbering 2 to 4 leverets. Those that survive are sexually mature Varying Tastes by the following spring, but very few Snowshoes eat a great variety of veg- survive for more than 2 or 3 years. etation, and, like their coats, their tastes There are many interesting aspects change with the seasons. They go from to the snowshoe, perhaps the foremost , grasses, ferns, and berries in the being that northern populations display warmer months to bark, buds, and tree cyclic fluctuations between abundance and scarcity, with peak-to-peak inter- 28 vals lasting about a decade. Population shenanigans). It is now a ubiquitous mam- density can vary between 1 and 10,000 mal in Massachusetts, thriving wherever animals per square mile! While it can find a little cover and lots of low has been ruled out (hare density influ- greenery (which pretty much describes ences predator density, not the other suburbia). Most authorities believe the way around) research continues to try to first ones stocked in the Commonwealth determine if these famous fluctuations, were released by hunters on Nantucket first documented in the 19th century, are sometime in the last quarter of the 19th influenced by disease, food availability, century. social issues (overcrowding), or some Hunters loved the EC because, unlike other factor or group of factors. The the New England cottontail (NEC), which species is known to suffer from a unique tends to “go to ground” immediately “shock disease” that can affect entire when pursued, this rabbit usually runs, populations and appears to be unrelated taking its pursuers on lengthy, circuitous to any pathogen. Afflicted animals suffer chases. During the heyday of wildlife liver degeneration and hypoglycemia, but introductions in the first half of the 20th the cause of the fatal syndrome remains century, more than 16,000 ECs were a mystery. transported from the midwestern states and released here, and another 4,600 Cottontail Issues were raised at a MDFW game farm and The most common rabbit in Mas- released. Today the EC can be found in sachusetts today is undoubtedly the every county of the Commonwealth and eastern cottontail (EC), the one you see appears to greatly outnumber and hold munching weeds in the backyard around more ground in all of them than the NEC, sunset; the one that mowed through all which is now extirpated from Dukes and your string beans and sprouting flowers Nantucket counties and may already be overnight last May; but also the one that absent from at least a couple of others. did not dig up your bulbs (because rab- The EC now ranges over most of the bits, unlike rodents, don’t dig up bulbs continent below the Canadian border, but and shouldn’t be falsely accused of such it appears to have evolved in the multitu- dinous edge habitats of the prairies and seems best adapted to mixed field/forest habitat. Conversely, the NEC appears best adapted to high density thicket habitats; those which occur ephemerally following abandoned ponds, forest fires, ice storms, tornadoes, hurricanes, and flooding, to name a few. Thickets are areas with high stem density, and this appears to be crucial for NEC habitat. High stem density areas where NECs may be found include young forests (re- generating after natural disturbances like those mentioned above, or after timber harvest); agricultural lands reverting to “old field” habitats; areas that have been mechanically cleared and are regenerat- ing dense woody cover (such as power- line cuts and railroad corridors); shrub While New England Cottontails are often impossible to positively distinguish from Eastern Cottontails unless they are in the hand, it is now very probable that any cottontail seen in a suburban setting rather than in (or in close vicinity to) extremely dense thicket habitat is an

Photo © by Bill Byrne Eastern Cottontail. 29 swamps and brushy areas near beaver has closed the gap to 30 feet. NECs seem flowages; dense upland shrub thickets well aware of their sensory limitations (composed of native shrubs, brambles, and do not venture beyond the edges of and greenbriar); and coastal shrublands the high stem density habitats that have with frequent wind and salt spray. cradled them for thousands of years. The It is unlikely that either species can live EC does not have this limitation, however. in contiguous, mature, closed-canopy A habitat generalist, it is better adapted to forest; they both need open-canopy fragmented forests and farmlands than its habitats, but one needs small openings, more specialized cousin, and it thrives in while the other can use any size open- the mixed field/forest edges of suburbia. ing. Civilization is prone to making big The NEC appears to require habitats of openings, and unlike nature, it doesn’t sufficient stem density and impenetrable- typically allow them to close up and ness that predators are not cause for alarm reopen again. unless they get within 30 feet. Both species are frustratingly similar EC vs. NEC in their looks, habits, and behavior. They As John Litvaitis of the University of New have two or three litters a year, from Hampshire so elegantly demonstrated March or April through September, five with his continuing research on the two to six young per litter. Like the snowshoe species (see our #4, 2002 issue), the EC hare, they switch from a summer diet of can pick up the airborne approach of a grasses and leafy vegetation to a winter at a distance of 70 feet, diet of bark, twigs, and buds. They can while the NEC, with its smaller, less effec- both jump 10-15 feet when they are in tive eyes, doesn’t react until the predator a hurry, and both can hit speeds ap- Photo © by Bill Byrne Research conducted on our cottontails to date indicates that the New England Cottontail can only compete effectively with the Eastern Cottontail in very high stem density, early successional habitats. This habitat is of limited duration; continual natural (fire, ice) or artificial (logging) disturbance is necessary tomaintain it. 30 Photo © by Bill Byrne Unlike baby hares, called leverets, which are born open-eyed and fully furred, baby cottontails are altricial, born almost furless and with eyes closed. This pair of young cottontails is about 3 weeks old. Interestingly, despite their differences at birth, our hare and cottontails take about the same amount of time to be weaned. proaching 20 mph in a dash. While home ducted from 1990-1993 found NECs in only range sizes of up to 40 acres have been 6 counties. The EC was found in 13 of 14 reported, the late MassWildife biologist counties. To our north, the situation is Jim McDonough, who conducted ground- not any better. A 2008 breaking research on cottontails in the survey found NECs in only nine of 23 sites 1950s, found the average home range where they were found in 2003, while size was less than 1.5 acres. He also found NECs in only 14 of 80 sites found the NEC bred later in the spring previously occupied in 2004. than did the EC, but springs being what Concerns about the NEC’s long-term they are in New England, it is doubtful population decline prompted the USFWS this provides the EC with any significant to propose the NEC as a candidate for list- advantage over the NEC. ing under the U.S. Endangered Species Act. But something has tipped the scales, It is no suprise then that the NEC is identi- something has caused the formerly wide- fied a “species of greatest conservation spread native’s range to contract and be- need” (SGCN) in the wildlife action plans come spotty, and the spots, based on the of every state within the NEC’s range, limited survey data available, to become including MassWildlife’s Comprehensive smaller, and in many cases to wink out Wildlife Conservation Strategies (state altogether. The NEC’s range has shrunk wildlife action plan) which you can view by 86%, and some 60% of the spots or online at www.mass.gov/masswildlife. “habitat patches” where it still occurs are now considered population sinks. These Habitat is the Key are habitat patches with characteristics The statistics on the NEC beg the that drew in NECs from some other patch, question: What is causing this popula- but are not of sufficient size or quality to tion decline? Just as “location, location, maintain a local, productive population. location” is the prime factor in real estate, Such poor quality habitat patches “drain” “habitat, habitat, habitat” is the prime the population rather than replenish it factor in supporting the NEC. John Lit- with new NECs. vaitis, a leading researcher of the NEC, In Massachusetts the NEC was once has concluded that the loss of the spe- found statewide. However, a survey con- cies’ primary habitats to development, 31 fragmentation, and forest succession and ), is now working together is its main problem. It would seem that with the USFWS and other conservation for the NEC, neither natural nor partners both public and private in the disturbances have created sufficient Rangewide New England Cottontail Initia- habitat to counteract these landscape tive. The Initiative is focused on creating changes and land practices. and restoring 1,200 acres of NEC habitat Adding to the NEC’s problem, there by creating 50 new habitat patches across is also evidence that the EC may be the species’ range. The target goal is to out-competing the NEC for habitat. The increase the NEC numbers by at least 720 NEC was known to use a much broader animals and support a viable, long-term variety of habitats prior to the introduc- population. The Rangewide NEC Initia- tion and expansion of the EC population. tive is just gearing up to begin in 2010 This suggests that the EC outcompetes and will use federal and state matching the NEC in most habitats except those funds over the next 3 years. with very high stem density (thickets). In addition to this habitat initiative, Since thicket habitat is of limited size and Massachusetts and its partner states and fleeting in duration, NECs must be able organizations will be trying to address to move on to the next patch when the another challenge: how to survey for one they are inhabiting begins to mature NECs and identify potential NEC habitat into something else. statewide. The root of the challenge is If the ECs already dominate much of the that there is no easy way to tell the dif- intervening habitats, then odds are good ference between living NECs and ECs that NECs will have to travel further – and (although there are obvious differences travelling through unfamilair in skull characteristics) so there is no way is always perilous – in their search for for biologists to solicit a voluntary army new, higher quality habitat where they of observer/reporters to help us keep will have more of an advantage. Even tabs on the situation (as we could with, though captive trials indicate neither say, robins, porcupines, or even garter species displays an advantage in physical snakes). Unless you have the rabbit in domination of the other, the EC is likely hand, it is almost impossible to examine more adaptable and competitive over a their often subtle external differences in broader range of habitats, possibly due sufficient detail to be certain of the spe- to its advantage in earlier detection of cies. About all you can tell at a glance is predators. Still, the NEC is vanishing from that if it has a white spot or blaze on the parts of its range where the EC is not forehead, it’s an EC, not an NEC, all of present, so factors other than competi- which lack this marking. Unfortunately, tion with the EC are involved. the converse isn’t true, since about half One possibility is that invasive plants of the ECs also lack this marking. may be a contributing factor in the NEC’s Fortunately, DNA testing of fresh pel- decline. One of the few dietary studies lets, like skull analysis, can be used to on the two cottontails suggested that accurately distinguish between the two the EC is adapted to a wider variety of species. In the past, MassWildlife used foods than the NEC. Is it possible then from roadkilled, injured, sick, and that the EC can feed on more of these harvested rabbits to survey our rabbit aliens than the NEC? Have alien plants species. Most of the skulls were volun- usurped so much of the habitat from tarily collected and submitted to us by native plants that the NEC can no longer the public. The surveys were conducted feed its provincial tastes? Currently we in 1979, 1981, 1991-1993, and 2000-2003. just don’t know. Future efforts to identify and monitor NEC occurrence within Massachusetts Management and Surveys and at specific management sites will So what conservation actions can be likely involve both skull collections and taken to stem and reverse the downward DNA analysis of pellets. Other conserva- trend of the NEC population and maintain tion efforts may include introductions viable and healthy numbers throughout of NECs from managed source habitats the range of the species? Massachusetts, or supplemental breeding sites (such as along with five other states (New Hamp- one we attempted to establish on Grape shire, , , Maine, Island in Weymouth in 1985). 32 One thing that will definitely be part of timber harvesting, brush mulching, our NEC conservation efforts is the cre- mowing, and prescribed burning (which ation of thicket habitat: the young forest throughout its evolution were provided and shrubland, high stem density habitat by the work of , floods, and for- that is not only crucial to the conserva- est fires). The NEC should, as the local tion of the NEC, but also a host of other species best adapted to the local (though species from insects to ruffed to now thoroughly fragmented) thickets, bobcats. This is where MassWildlife’s For- be able to hold its own in competition estry and Upland Habitat Program takes with the EC flatlanders in this specific center stage. Among its primary goals for habitat. The habitat patches will need all forest lands controlled by the agency to be a minimum of 10- 25 acres in size, is to bring 15-20% of that forest habitat to and ideally adjacent to or connected to a young age through active management each other so that animals can disperse and timber harvesting. safely between them. While active forest management Questions about the distances between through logging is sometimes contro- patches and how they relate to NEC sur- versial, it is necessary to maintain forest vival must be answered to understand diversity – and forest is the primary habi- how best to increase and support NEC tat of New England. If we don’t conduct populations. As their ephemeral habitat this kind of forest management, we risk is lost or degraded due to development, losing the natural diversity of our native fragmentation, and forest maturation, the wildlife species. A quilt or mosaic should NEC will continue to face many potential not be made of identical components, and threats on a landscape that must now be, neither should the New England forest. It to the NEC, an alien countryside the likes is as simple as that. There is considerable of which their evolution in New England incentive to increase the pace of young could never have prepared them. forest creation when the NEC seems to Stay tuned. The unfolding story of be disappearing so rapidly. New England’s lagomorphs is far from The NEC can be conserved on man- over.... aged habitat (thicket) patches through Photo © by Bill Byrne 33

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