ABC'S: ANIMAL BEHAVIOR

CONCERNS & SOLUTIONS

A Question & Answer Forum For Animal Professionals

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Welcome to the ABC's! Animal Behavior Concerns & Solutions is an animal behavior column written by animal behaviorist and animal trainer, Diana L. Guerrero. This section is dedicated to animal training techniques for all animals and pets, and topics related to operant conditioning and reinforcement. This column discusses a North American River Otter (Lontra canadensis) behavior evaluation and otter training. For pet training please visit the pet sections, see our pet behavior booklets in the shop, or click here for enrollment information for classes and teleseminars.

North American River Otter (Lontra canadensis)
Animal Behavior Evaluation and Otter Training

QUESTION
We have an animal that sucks and chews on his tail. Can you recommend anything to address this matter?

BACKGROUND
This behavior has been exhibited by this animal since he was at least six months old, and possibly longer, and is a habit that has been ongoing for over three and a half years. The tip of the tail is currently hairless and raw. The behavior is described as constant and present throughout the day unless the animal is eating. No known triggers were described.

Currently this animal is housed with another animal of the same species and age but of the opposite sex. She is dominant. He was hand-reared from the age of 3 days by humans but the weaning date was not specified. He is described as being underweight, fearful and unsure.

The animal received some training at 3 months of age, however no details about the training parameters or management operations were described. He is reinforced with food rewards and vocal bridges.

The animals get enrichment 4 to 7 times a week but this particular animal also shows no interest in enrichment and has a dislike for the water. No further information on the type(s) of enrichment was provided. The exhibit where he is housed is approximately 2/3 water with 1/3 land. There are plants and trees and other greenery. The animals share night-quarters and can only be separated if they have to be.

The animal is thin and reacts fearfully during stress situations. He reacts adversely to male keepers but is amiable to females. He will not listen to male keepers and will bite them if approached. He has been cleared for fungal infections but no tests for allergies or other abnormalities have been conducted.

Unfortunately additional information requested on this case was not received for this evaluation. In the process of doing an assessment it is often critical to have details regarding the behavior and the circumstances where it first occurred, and any changes that accompanied or occurred during the time. Conspecific relationships and subtle behavior is also important. Ravenous eating behavior, aversions, other stereotypes, and noted trends help me to narrow the possible triggers for any behavioral challenge.

ADDITIONAL NOTES
River otters spend a large portion of their time out of the water unlike some of their cousins. They spend time rolling on the ground, rubbing on logs and on other vegetation near their sprainting sites. Their food consumption can be up to 20% of their body weight (in the wild) and they are active playful critters. They are noted for having a wide range of activity cycles --crepuscular, nocturnal and sometimes diurnal.

High activity animals are challenging animals to maintain in a captive environment. They need activity to displace their energies and a nutritional balance that provides them with the right fuel. The dynamics within their enclosure, with their conspecifics, and the proximity to the public can create additional stresses or complications if not appropriate for the particular animal.

Food consumed by this species in the wild varies from a variety of different fish, aquatic invertebrates, amphibians, baby birds, rodents, larvae and other insects, and a variety of vegetation. In the captive environment diets often to vary from fish, horsemeat, canine or feline diet, vegetables, and supplements. Day old chicks, pinkies, cooked eggs, worms, and a variety of other tidbits can be additional goodies. Roughage is very important to have in the diet. Fish, chicks, and carrots and invertebrates or crustaceans are often given to provide this.

Otters can be found in a variety of different. Pups are not usually weaned until between four and five months but are introduced to swimming at around two months. Unfortunately, hand-reared animals tend to be weaned early and behavior abnormalities from early weaning can emerge. These behaviors can manifest as the sucking behavior of various body parts.

SUGGESTED ALTERNATIVES
Veterinary evaluation.
As usual, a veterinary and nutritional evaluation should always be done to rule out parasites, bacterial or fungal infection, allergies, or other contributing factors. Deficiency within the diet can cause skin and coat problems or food allergies might be contributors.

Because the animal has a reluctance to go in the water he may have a problem with his coat condition. It should be smooth, soft and shiny when dry and spike up so the moisture runs off when wet. If the coat is matted down it may be getting saturated and contributing to the animals distaste of water. If that is the case, check for your dietary regime and imbalances in the environment. (See below) Be sure to check water quality and cleaning product residues.

Since the animal is also underweight I would encourage you to evaluate the diet and have your veterinarian check for other contributing factors. (Also see social activities.)

Log social activities and nuances.
In addition to being underweight, this animal is described as being unsure and fearful. Dominance by another animal may also contribute to the problem. This and other stresses could be displaced through the sucking behavior. Keep a log of which animal goes through the gate into the night quarters first. You'll be checking to see if there is any subtle displacement, note who instigates play, and other details.

Volunteers or docents could conduct scans or keepers could form a simple ethogram for use during am/pm release. Design these to be simple check mark forms with details and parameters clearly defined to make this easy. Note if the behavior is triggered by certain events, times, or the presence of individuals (keepers, public).

Also note what vocalizations are occurring between the animals. This will help determine what the general state of the animals are and help discern what may be happening. See the references below for detailed assistance on defining vocals.

Exhibit design.
Captive river otters do better with more land mass. In Duplaix-Hall it was estimated that the land to water used ratio would be 4:1 (for 15 X 10 enclosure). The current exhibit appears to need alterations based on the description. Perhaps an island or other adaptations could be made to create a better balance.

Make sure you have enough land area provided and associated support furniture within the exhibit. Check the ratio and consider including a private den with separate access, or at the very least an area where the male can be away from the female.

Grooming areas for rubbing & rolling.
Be sure to provide ample areas an opportunity for the animals to keep their coat condition optimal. You could include turf squares, shrubs or browse, bristle brushes, bristle brush mats, rocks and logs. Make sure there are enough of these throughout the exhibit so that one animal does not monopolize them and create more stress. Other terrain should include dirt, sand (not too fine to avoid coat condition interference), and could include occasional ice chips or snow.

Latrine areas.
Otters will normally maintain areas for sprainting. Be sure to allow some of this to remain within the exhibit as complete cleaning could add to the stress of some animals. Note particular marking habits and see if there are any conflicts in these patterns.

Novel objects.
Otters are naturally inquisitive and a large portion of their time in the wild investigating new objects. Be sure to create a complex environment through enrichment devices and activities. Make sure that enrichment occurs daily even if the one individual fails to show interest. You may just need to occupy the other resident animal. Use multiple sites and multiple types of enrichment (olfactory, tactile, etc.,) both in the water and on land.

Topical deterrent.
Because this problem has been in existence for so long, and because of the importance of coat quality in otters, I am hesitant to recommend using a topical deterrent. Tabasco sauce and bitter apple® have been tried with this animal already without success.

However, this tool may be an option to consider again if you locate the triggers. It could be used as a last ditch attempt to see if it will assist in deflecting the behavior IN COMBINATION with other strategies.

NOTE: Always be sure to test that the animal has an aversion to a topical deterrent first. In the otter's case it would be better to use a cream topical and it would have to be applied frequently.

Other remedies.
The earlier behavioral problems are addressed the easier they are redirected or extinguished. Since this behavior has been ongoing for so long it may be very difficult to extinguish. In severe cases of self-mutilation success has been gained through the use of alternative remedies or pharmaceutical intervention IN CONJUNCTION with behavioral therapy.

I would caution you again pharmaceutical intervention since it often only masks the symptoms of an underlying problem and can have intense side effects on the animal. Such applications should only be considered if after 12 weeks of consistent application of methods in extinguishing the behavior have failed….and even then you may want to just live with the problem.

Last thought.
You may also want to seriously consider offering an area for the male to retreat too or try some temporary separation and variety in your management scheduling to see how the behavior is effected. Changes should be apparent through the ethogram and other observations. Check your records to when he was first noted as chewing and sucking to see if it corresponds to his introduction to the female, weaning or other significant event.

SUGGESTED REFERENCES

Beckel. A. 1982. Behavior of free-ranging and captive river otters in North-Central Wisconsin. Ph.D. thesis. University of Minnesota.

Beckel, A. 1977. Otters: The journal of the Otter Trust.

Chanin, P. 1985. The natural history of otters. Facts on file. Croom Helm.

Chapman, J.A., & Feldhamer, G.A. eds. 1982. Wild mammals of North America: biology, management & economics.

Duplaix-Hall. N. 1972. River otters in captivity in Breeding endangered species in captivity. Martin, R.D. ed. pp. 315-327..

Foster-Turley, P. 1990. Otters: an action plan for their conservation. International Union for the Conservation of Nature.
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Fowler, ME. Editor. 1986. Zoo & wild animal medicine. Saunders & Co.

Harris, C.J. 1968. Otters: A study of the recent Lutrine. William Clower & Sons, Ltd.

Harris, C.J. 1968. Otters. Weidenfeld & Nicolson.

Kruuk, H. 1995. Wild otters. Oxford University Press.

Maehler, Amy. 1997. Not a barrel full of monkeys, but a bucket o'laughs! AAZK Animal Keepers' Forum. 24(11)483-485.

Martin, R.D. ed. 1975. Breeding endangered species in captivity. Academic Press.

Markowitz, H. 1982. Behavioral enrichment in the zoo. Van Nostrand Reinhold.

Melquist, W.E., & Dronkert, A.E., 1987. River otter in wild furbearer management and conservation in North America. Novak et. al. eds.

Partridge, J. ed. 1995. Husbandry handbook for mustelids. Association of British Wild Animal Keepers.

Reed-Smith, J. 1995. North American river otter husbandry handbook.

Reuther C. & Rochert, R. eds. 1989. Proceedings 5th international otter colloquium. No. 6 Hankensbuettel.

Sequeria, Gina. 1993. Evaluation of enrichment devices for captive North American river otters (Lutra canadensis). AAZK Animal Keepers' Forum. 20(10)359-363.

Are you a reader with a question? Be sure to submit it--and good luck in all your training endeavors!

About the columnist: Since 1978 Diana L. Guerrero has worked professionally with both wild and domestic animals. Guerrero has been affiliated with, and certified by, a variety of animal programs in the USA and Europe. Based in California, she writes, consults, and speaks. Information on her animal career programs, training courses, and her books {What Animals Can Teach Us about Spirituality (SkyLight Paths, 2003), Blessing of the Animals (Sterling, 2007), Help! My Pet is Driving Me Crazy (Guerrero Ink, 2007), Animal Disaster Preparedness for Pet Owners & Pet Professionals (Guerrero Ink, 2007)} can be found in this web site and in the shop. Questions for Guerrero should be submitted via the blog comments or membership forum.