Jack Be Quick!
The “Jack be quick” line from a favorite children’s nursery rhyme isn’t referring to jackrabbits, but it does in one word explain how jackrabbits make their living. Jackrabbits may be the quickest, longest jumping, most maneuverable critter we have in Iowa. That’s right, I said in Iowa. A lot of people have probably not heard of jackrabbits in Iowa, but the fact is that there are populations of white-tailed jackrabbits in a number of locations in the state and some are even seen in Dallas County.
Everyone is familiar with the cottontail rabbit that is so abundant across the state in both town and country. The white-tailed jackrabbit is different from this relative in a number of ways. The white-tailed jackrabbit (jackrabbit) is a “hare” being more closely related to the snowshoe hare from the northern United States than to a cottontail. The jackrabbit is a large mammal weighing up to ten pounds and being almost two feet long – much bigger than a cottontail rabbit which will weigh about two pounds. The jackrabbit has very long ears (up to six inches) that have black tips on the ends. Jackrabbits are brownish-gray in color in the summer and change to mostly white with a very light gray back and still keep the black ear tips in the winter. Being hares, jackrabbits are born with fur and with their eyes open while cottontails are born naked and blind. While cottontails are fond of wood lots, brushy areas, and other habitat with a lot of cover, jackrabbits are creatures of open spaces. They prefer short grassy areas with very little cover. They rely on their eye site to spot danger and on their incredible speed to out run it.
We are most fortunate in Dallas County in that one of our local residents, Mike Thalman, has been studying white-tailed jackrabbits in central Iowa for a number of years, and he has amassed many photos of these animals along with a wealth of knowledge. Mike has shared several of his photos and some of his experience in this article. For example, while the books state jackrabbits can run 30 to 35 miles per hour, Mike has clocked one at 47 miles per hour. He has measured 20 feet spans from touch down to touch down points in their leaps. Mike has watched them clear the tops of fences as they speed away. He has noticed that instead of running in a straight line, they often zig-zag if they are pursued by a predator such as a coyote. This maneuver makes it more difficult for the predator to catch the jackrabbit plus if gives the jackrabbit the opportunity to check behind itself to see where the pursuer is. Mike has also notice that jackrabbits usually run in a big circle ending up close to where they started. The most jackrabbits Mike has seen in Iowa in one day is 59, and if anyone can top that please let me know.
Jackrabbits were historically inhabitants of the western wide open spaces. Tall grass prairie such as that which covered most of Iowa would not have attracted them. As Iowa was settled and the prairie was opened up and pastures and other short grass areas were developed, jackrabbits started moving into the state from the west. The highest populations have always been in northern Iowa. Monoculture row crops, such as corn and soy beans, are also not attractive to jackrabbits and so, today, with the move to this type of ground cover and with the loss of pasture land and fence rows, jackrabbits have been relegated to smaller and smaller areas to call home.
Where in Iowa can you look for jackrabbits? Mike Thalman would tell you that just about any large grassy field could be productive at some time of the year. Jackrabbits will expand their range outside of their breeding territories in the winter when snow cover has “opened up” the areas they can safely inhabit. While not in typical territory, Mike found one just north of Minburn and another just east of Adel in Dallas County. I have seen several north of Dallas County near Rippey. Most of Mike’s sightings in central Iowa have been made at either the John Deere Manufacturing Company’s land in Ankeny or at the Iowa State University’s Research Farm west of Ames. Both of these areas have large tracts of grass that is kept mowed and provide excellent habitat for jackrabbits. It is important to note that both of these sites are not open to the public and with new safe-guards and concerns in place, trespassers will not be tolerated. Other sites in Iowa that have jackrabbits often include airports and golf courses. The Spencer Airport and the Waterloo Airport are known to have jackrabbits living along the runways. Again, no one should go looking for jackrabbits on airport ground for a lot of reasons including that it would be extremely dangerous to you and others and it is illegal. Anyone truly interested in seeing jackrabbits in Iowa would probably be rewarded by spending time driving roads through short grassy areas especially in north-west Iowa.
Mike Thalman believes the numbers of white-tailed jackrabbits in central Iowa are dropping. He knows that part of the reduction is due to loss of the specific habitat type needed. He also believes that fewer jackrabbits is directly linked to an increase in the number of coyotes. He has monitored jackrabbits in an area where the “jacks” were apparently living in harmony with red fox. Coyotes eventually moved in and drove the fox away, and the jackrabbit numbers also plummeted.
The reproductive cycle of jackrabbits is also not as productive as that of cottontail rabbits, therefore, they are not able to recover population losses as quickly as cottontails. Jackrabbits breed from February through early July. They usually have three or four young per litter. They may have several litters per season. While this may sound lot a lot, cottontails may have eight young per litter and may have four litters per season. Also, female cottontails can give birth the same year they are born. There is no evidence that female jackrabbits can breed before they are at least one year old.
The ultimate success of white-tailed jackrabbits in Iowa is questionable. Species that require a special niche to call home are always more vulnerable than those that can readily adapt to change in their surroundings. We can help these border-line species by trying to preserve areas know to harbor them. With a little effort and with knowledge accumulated by people like Mike Thalman, we may be able to keep jackrabbits in Iowa for a long time.
If you know of white-tailed jackrabbit populations, especially in central Iowa, please call or email me so that I might update our knowledge about this fascinating creature. (phone: 515-465-3577 or email: bobmdallas@iowatelecom.net) Please send us details of your Dallas County jackrabbit sightings. Include the date, time, and location in your report.
Bob Myers
Park Ranger/Biologist
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