From November 2011

Reuniting and Fostering Wildlife

By Anne Miller (reprinted from the November 2011 IWRC newsletter)

A ground-breaking session on Reuniting and Fostering Wildlife was one of the highlights of the IWRC Symposium in Ft. Lauderdale this November.  A panel of seven speakers described methods of reuniting and fostering most species of native North American wildlife in a series of half-hour programs that provided persuasive proof that reuniting healthy young wild animals with parents should be ‘an obligation, not an option’ in nearly all situations.  The presentations underscored the fact that juveniles raised in the wild by their own parents learn valuable skills such as prey recognition and predator avoidance that are hard to teach in a rehab setting.  Older juveniles also benefit significantly from the protection of parents during the vulnerable period while they are becoming independent.

The case was made that the practice of keeping healthy juveniles that could be reunited causes severe overcrowding in many wildlife rehabilitation centers, leading to unnecessary expense, overcrowded facilities, and staff stress and burnout. Wildlife rehabilitation centers that reunite all healthy juveniles see immediate benefits from the much smaller number of animals requiring treatment, allowing them to provide the best quality of care for those animals that cannot survive without their help.
The session was sponsored by the Humane Society of the United States, and was co-chaired by Laura Simon, of the HSUS, and Anne G. Miller, author of ‘Calls of the Wild:  Using Recorded Calls and Other Tools to Reunite Juvenile & Adult Raptors’.  Anne Miller opened the session by demonstrating that reuniting wild animals with their parents ensures the greatest chance of survival for dependent young, but that we need to understand the biology of a species in order to ensure a successful outcome when reuniting.  Featured Speakers included Jay Holcomb, Director Emeritus of International Bird Rescue, speaking on Reuniting Ducks & Geese; Rebecca Dmytryk, of WildRescue, speaking on Reuniting Raptors; Elizabeth Hanrahan of Ocracoke Wildlife Rehabilitation, speaking on Reuniting Songbirds and Shorebirds; Diane Nickerson, Director of Mercer County Wildlife Center, speaking on Reuniting Fawns; and John Griffin, of Humane Wildlife Services, speaking on Reuniting Small Mammals in the Urban Setting. Laura Simon wrapped up the program by making a persuasive case that we need a new paradigm where rehabilitation success is measured not in terms of intake/ release statistics, but in the number of animals successfully reunited and kept out of rehab facilities.
The session was followed by a planning meeting also sponsored by the Humane Society of the United States, and attended by all of the speakers, aimed at organizing a nation-wide campaign to promote the practice of reuniting healthy young animals wherever possible.  The group is actively recruiting experienced wildlife rehabilitators who are interested in cooperating in a nationwide network to research and develop viable protocols and to help promote reuniting and fostering wildlife as an essential practice for wildlife rehabilitators.  For information, contact Anne Miller at

Thoughts on Imprinting vs Socialization

Aardvarks to Zebu: Post 2

Every so often we choose a challenging rehabilitation question and poll two to four experts on the topic.  This time, we chose “Explain the difference between an imprinted or socialized animal, or are they the same thing?” and asked it of a behavioral scientist who works at an education and behavioral research facility with captive canids.  If you have your own burning question, email me at  The question just might find its way into a future post!


Aardvarks to Zebu:

Wildlife Rehabilitation Quandaries and Conundrums


Explain the difference between an imprinted or socialized animal, or are they the same thing?

Pat Goodman – Wolf Park

ABSTRACT:  Imprinting and Socialization are closely connected behavioral events.  Imprinting occurs during a limited period of time, typically for a short period after an animal is born or hatched.  It has a profound effect on the young animal as it matures, determining to what species the infant will show social behavior, and sometimes determining from what species the animal chooses its mates.  Knowledge about imprinting is necessary in captive breeding programs if the animals so reared are to be able to choose and mate normally with their own species rather than choosing individuals of the same species as their foster parents.


While there will be variation depending on the species in question, socializing an animal means to rear, or interact with it in such a way that it can use its repertoire of social signals with other animals.  One of the prerequisites for socialization to a species other than its own is a reduced flight distance from that species.   Usually an animal is socialized to its own kind by interacting with its parent or parents, and other members of its social group.  As it matures, its experience and skills in social interaction expand to include others besides its parents and its siblings or other age mates.  Sometimes an animal acquires the ability to respond to the social signals of animals not of its own species, typically through either rearing by foster parents of a different species, or, later in life, repeated exposure and opportunity for non-damaging interactions with another species.

Often socialization to species other than its own is best begun when the animal is very young.  Socialization to humans later in life can be more stressful and risky for the animal and human involved, and the range of the social repertoire that the animal shows to humans may be only a fraction of what it would show to its own kind.  Wolf Park’s bison, for example, are somewhat socialized to humans through repeated contact paired with special food such as apple slices or sweet feed, and the opening of gates to greener pastures.  We do not make attempts to socialize them extensively.  They do a little bit of greeting occasionally, sometimes solicit food, and sometimes warn or threaten us.  Their social signaling to us is limited compared to the social signaling between us and the wolves.

Imprinting is not, itself, socialization, but it may determine what a young animal becomes socialized to.  Imprinting takes place during “critical periods” in the development of an infant animal.  Often this period starts very shortly after it is born or hatched.   During this time, the infant learns very quickly and very thoroughly to recognize a blueprint for a parental figure.    Once this sensitive period is over, socialization to other species, while theoretically still possible, tends to be more labor intensive, less complete, or even impossible given the limitation of resources in the real world – time and skilled caregivers.  It also tends to be less effective, less enduring, and may involve more hazards to the animal being socialized and the one doing the socializing.  Successful socialization to an animal of a different species, or even its own species, once the sensitive period for imprinting is past, may involve isolating the subject from its own species, and making it dependant on a member of another species for all its social contacts.

In some species this early imprinting also affects mate choice later on, if, in addition to recognizing its parent, the young animal learns to prefer an animal matching its parent’s blueprint as a mate when it matures sexually.  Typically it does not imprint on its individual parent as a future mate, but will prefer an animal of the same species as its parent.  If it has a foster parent not of its own species, it may reject mates of its own kind when it is an adult, and court members of the same species as its foster parents.  Some newly hatched birds can even imprint on inanimate models as parental figures.

In precocial species, which can run around shortly after birth, the infants often show a readiness to follow something that moves in their immediate vicinity.  An infant can develop a strong interest in an object and then be less interested in other objects to imprint on.  Often this attachment can be enhanced by food rewards.   Normally such reinforcement is provided by the mother, who may also reward infants with warmth and pleasant social touch.

The length of this sensitive period varies according to species, and to some extent, on the particular circumstances.  According to the Oxford Companion to Animal Behavior (David McFarland, editor, p. 303) “Domestic chicks kept in groups cease to follow moving objects 3 days after hatching, but chicks reared in isolation remain responsive for much longer.  In natural conditions the young birds would become imprinted upon one another; chicks and ducklings tend to stay close together, even in the absence of a parent.”

As young animals develop, they often begin to explore, and at some point many of them show signs of neophobia, fear of novel things.  This fear can interfere with the young animals’ abilities to form attachments to other animals, including humans.  At Wolf Park we discovered that we must take wolf pups away from their mother and start hand-rearing them at 10 to 14 days of age.  It is not enough to leave them with a wolf mother who will permit trusted humans to visit daily and handle the pups.  The mother-reared pups will show some shortened flight distance from us as they mature but they will not show much of their social repertoire to us and they will not solicit many affiliative interactions; rather, they tend to stay out of reach.  If, however, we take the pups away from the mother, but keep the litter together, so that they get near constant contact with their own litter mates for wolf –to-wolf socialization, and give them about 2000 human hours of social contact, which takes more than one human, starting from their removal from their mother at 10 to 14 days old, until they are 16 weeks old, we have wolves who will be able to show the full repertoire of social behavior to their own kind and almost their full repertoire of social behavior to humans as well.

Historically, researchers studying the biology of behavior used imprinting to do experiments that required cross fostering, producing young that were thoroughly socialized to a species not their own.  Once these young animals were mature they were willing to mate with members of their foster species, and, in turn their offspring often demonstrated which behaviors were inborn, and which behaviors were learned during individual development.  Such research was done a lot with birds, which often imprint on their foster parents’ species as future mates.  Such sexual imprinting seems to happen less often with mammals, according to the Oxford Companion to Animal Behavior, but it can occur.  Wolf Park once received a wolf pup rejected by his mother, and also he was the only survivor of his litter.  Reared in a children’s zoo until he was five months old he had plenty of exposure to humans, but no experience of canines until he came to Wolf Park.  I do not recall him ever showing courtship to other wolves, though several of our females found him attractive and courted him.  He preferred to court humans, and vigorously rebuffed female wolves.

To sum up, imprinting is a type of learning restricted to certain periods very early in the development of animals.  During these sensitive, or critical, periods, an animal’s preferences for social companions, and mates may be determined and it may be difficult, or impossible to change them later in life.  In some species, food preferences, and preferences for a certain kind of habitat may also be established very early in life.  Animals may be able to imprint on more than just one species.  Konrad Lorenz and his students were able to “infiltrate” their goose flocks and study the birds’ behavior at very close quarters by imprinting goslings on humans as well as on geese.

At Wolf Park, whose founder, Dr. Erich Klinghammer, regards Lorenz as a friend and mentor, we do something similar with wolves.  Since our wolves are not candidates for release in the wild, and so need not be fearful of humans for their own safety, this type of rearing facilitates our husbandry procedures throughout their lives.  It makes additional environmental enrichment opportunities available, since some of our routine maintenance can be a social occasion in which the wolves participate willingly.  It reduces the stress of being in captivity and contained in fairly close proximity to the visiting public.  Routine care, and even some emergency medical care can be accomplished without tranquilizer guns, nets, etc.   If a wolf is driven from its pack, or if it outlives its pack members and we cannot provide it with another compatible wolf as a companion, humans may be that wolf’s only source of friendly social interaction, especially for social touching.

Imprinting does not guarantee that a wolf will always be safe and easy to handle.  It does result in a wolf that is typically open to life – long learning about, and, we hope, improvement of its social skills with humans.  This openness is achieved and maintained by carefully monitoring our interaction history with wolves, use of some classical and operant conditioning, and attempting to understand their physical perceptions and emotional states, plus their individual developmental and history of personal experience with humans and their environment.

President’s Report Fall 2011

From the President’s desk
I am writing this letter from my aunt’s garden in England, for the most part hearing strange bird calls with the odd one I recognize. All punctuated with that odd sound squirrels make, yes I do recognize those, our grey squirrel, now a problem species here in the UK. I have been in Ireland  to attend the Irish Wildlife Rehabilitation Conference and present the IWRC’s Basic Course to a small group of Irish wildlife rehabbers. What a thrill for me to teach the course, but of course I was somewhat  concerned about the differences in species. North American species present no problems, however, my knowledge of species around the world is sufficient to recognize families, but not necessarily species. So my first port of call was the Irish Natural History museum in Dublin. One floor is devoted to the species of Ireland, all collected, read mostly shot and mounted, by the Victorians. It was interesting to see the dates on the specimens which ranged from the mid 1800’s into the early 1900’s. In many specimens, the bullet holes were evident.  It was sad to see, and as one person pointed out, it is locally called the dead zoo. However, it did provide me with a valuable look at the range of species Irish wildlife rehabbers deal with. Not surprisingly, many were either the same or close relatives to those in North America. Sometimes the names stumped me, but looking at the scientific names helped. So, the northern diver is North America’s common loon, Gavier immer. The reality is that the principles of professional wildlife rehab are the same all over the world. But now I was prepared and could use local names and give related species as I presented IWRC’s flagship course. It was such a pleasure to present  it to our colleagues. The course finished, we had a bat box making session. Mine is going to be winging its way over the pond, if I can fit it in my luggage. And that will be quite a challenge.
I then met up with fellow IWRC board member Adam Grogan and attended the conference itself. I had been asked to give several talks, which were fun to prepare and present. The first day was a general rehabbers day, a great chance for the rehab community to get together. The second day was geared to the veterinary community, nurses and vets, with continuing education credit for attending. All in all, it was simply wonderful, of course the accents were amazing too. Next leg, I travelled with Adam to Mallydams near Hastings in southern England. This is one of the RSPCA’s wildlife rehab centers. Again, I presented the Basic Wildlife Rehab course to a small group of rehabbers.  Nights were also special, local pubs and pub meals, pub quizzes, and badger watching. I had the privilege of seeing 5 wild badgers. What a thrill. This week I have so much to look forward to also with visits to my old stomping ground, London Zoo, and several rehab centers, along with a meeting about the plight of oiled birds with the RSPB. I am looking forward to an update on that awful disaster on Tristan de Cunha. The mortality will understandably be high as this is a very remote region with few resources.
It is a treat to meet a so many rehabbers, Irish, English and Scottish, plus a Polish veterinarian! No matter where we are in the world, rehabbers are all committed to the same things; caring for the wildlife we admit, relieving pain and suffering, and growing healthy vibrant youngsters up to become good wild citizens, heading off to live free and wild and make babies.
Back in North America, the Educational Symposium is coming up fast. You can check out the IWRC website for the details. Of course many IWRC members are still inundated with patients. Hopefully you can hand over any late admissions to team members and join us in Florida, the line up is looking great. One other activity we need to work on is the Annual General Meeting. This is required by IWRC by-law and is also an opportunity to report on the state of IWRC. It is also the time to have nominations from the floor for board membership.  If you have skills and time to share them, please consider joining the board. The thing to remember is the time factor. This is a working board and to keep IWRC vibrant, fiscally responsible and relevant to our community takes work. Meetings, both in person and by phone or skype, keep us connected and moving forward. Committee membership is required, so you will need to factor those commitments in if you are considering joining. Plus there is a financial commitment. IWRC does not cover costs associated with meetings. Currently we have a weekend meeting in March or April, plus a meeting at the Symposium. Given the amount of work we cover, there is also a potential to reinstate a third in person meeting. Most months we also get together by phone or skype. The committees also often use skype for their meetings, which does help with cost.  Do you have the time? Can you bring needed skills? Talk to Kai for further information or submit a nomination at
The Basic course  review is coming along. I will ask the committee involved about the images they are seeking and let you know, in case you can help. Digital photography has really revolutionized our world, allowing us to share our cases, both in seeking help and advice, as well as helping our colleagues learn from our experiences.   So please keep taking photos and sharing them with us all.
Talking of courses. The Course Development Committee is really steaming ahead with several new courses in the works. We will prepare a review of them for presenting at the Symposium and then have them available for all IWRC members in the website.
Requests for input to various research projects are occasionally sent to Kai. She will be placing them on the IWRC website. Please have a look, they may be things that are of interest to you personally, and of course, help our wildlife.
Finally, do take time to smell the roses. It is so hard to keep that space for you when every where you turn there is a mouth open waiting for food, a cage to clean, a phone ringing. We are such a special bunch of people because we do give so much of ourselves. From experience however, I can tell you that taking special time to nurture ourselves is well worth it. I am now off to smell the roses! See you in Florida.
PS Are there any veterinarians interested in joining IWRC’s Board of Directors? Please contact me asap.

President’s Report Summer 2011

Dear Colleagues
Summer is at its height in the Northern Hemisphere and rehab centers are loaded with babies and injured adults to care for, and a phone that never stops.  We often forget to take time to care for ourselves.  Having been there and gotten many tee-shirts, I can only ask you, my dear colleagues, to try and take time for yourselves.  Some years ago, I wrote a talk entitled ‘Stress, burnout, compassion fatigue, and adrenal fatigue – the dark side of rehab’ (yes it is a bit like do as I say and not as I do!).  In preparing for this, I asked colleagues on a rehab chat line for input, what are the worst issues you face and how do you de-stress.  One reply still resonates and I have endeavored to use it in my life.  This wise person takes time for an unbreakable date with her husband each evening, meeting on the deck at 6pm, time for being together.  My translation is nibbles, a drink, maybe a fruit juice spritzer, and M*A*S*H re-runs with my husband, so calling me between 5 and 6pm may not be a good thing.  We chat, catching up on the day and deciding what supper will be if there are no left-overs in the fridge.  Magic!  I look forward to this special time and always feel recharged afterwards.
IWRC has been busy with planning for the 2011 Symposium.  Kai and Kim will let you know the details as soon as the plans are finalized.  I look forward to meeting you in Florida this November.  Maybe we can try meeting for a drink at 5!
Bookings for courses are also keeping us busy.  Don’t forget to check out the in person courses that may be coming to your region.  On-line courses are also being revamped and released.  There are several new and very exciting courses in the works.  Kai will let you know more next week.
Instructor Team
Did you know that all of IWRC’s instructors are Certified Wildlife Rehabilitators (CWR)?  We, yes me too, have all sat this on-line exam, designed to challenge our knowledge and ensure that a pass really is quite an achievement.  IWRC is also proud to welcome new instructors on board.  If you are interested in preparing for this exam, the Basic Course is a great start.  Check out the locations of up-coming classes.  None near you?  How about hosting one?  Contact Kim at
The Basic Course needs your help (and Nutrition Course too).
This wonderful course is in need of an update which will be tackled later on this year.  But we need images to update the PowerPoint.  Can you help please?  Topics cover a wide range, as any of you who have taken this class know, and you probably remember that many of the photos are looking rather ancient!  So, this summer, take lots of photos and share your high quality digital images with us and other rehabbers.  Topic we need digital images for include: facilities, caging, flight caging, housing, diseases, general images of wild animals, babies of all sorts, injuries, release sites and releases, laboratory set-up, digital X-ray images, safety equipment, and any thing else you would like to share with us.  We would also like to to place some of the images not used in the course in the IWRC Members site as a resource available for browsing.  Please let Kai know who took the images so we can ensure they are acknowledged correctly.  Email images to
The Nutrition Course is also up for review and I would like to bring more images into this course also.  So think about any photos that would be of use to illustrate nutritional issues.  Have you received an animal with severe nutritional deficiencies?  How about feather damage?  Fractures?  Please take those photos and send them to Kai.
Talking nutrition, calcium is often an underdone component of our young wildlife diets.  You can simply use your egg shells for your charges.  If they come from boiled eggs, simply dry them and grind them up.  If uncooked, bake them for 20 minutes at 250°F, grind them up and store them in a container.  Place a little egg shell in all your cages allowing your charges the chance to add calcium to their diet as needed.  Deer antlers are great calcium sources for small mammals.
Thinking about courses, a new series of webinars are going to be added to the IWRC Members section.  The first one should be out next week.  It is the first in a new series called ‘Almost everything you wanted to know…’.  These webinars address topics we all need to know something about, the first one – Needles and Syringes.  The next – Reading a pharmaceutical label.  I have to admit, I learned lots too as I pulled them together.  Plus it was fun to do these units.  Are you interested in helping?  One I am working on is – how to identify that white stuff in that bird’s mouth.  Contact Kai.
In the works are a special series in the ‘Almost everything…’ group – Wildlife Disease Webinars.  We are hoping to enlist veterinary students to help prepare them.  However, we need your help too.  Let us know what wildlife diseases are of concern in your area.  What species are affected and what common names are used for this disease.  Also, do you have any contact with your local vet school?  We would love to ensure that they are in our database.  This series could be a great class project and the benefits ongoing for years to come.  Email Kim at if you have a vet school contact to share.
The webinars are all going to be translated into French and Spanish.  However, I don’t want to wear out our 2 volunteer translators, so do you know someone who can help with these languages?  It would also be useful if they are prepared to simply review the translation.  My hope is that we can also translate the webinars into other languages, Mandarin and Cantonese being two languages that would be so exciting to offer these in – OK I know, dreaming in Technicolor again, but if we don’t, nothing changes.  So if you dream too, and can help, let me know.
I was really excited when Kai asked me to look over the book titles she was considering purchasing for the on-line store.  There really is nothing like a great reference book on the shelf, something to turn to for help and ideas.  Let her know at if you need other titles.  I am looking for a new drug formulary.  What ones do you find most useful?
A new Database for State, Provincial, and Territory contacts (and beyond)
We are developing a new database for our membership of all the contact information, current regulations for registering a rehab center, relevant wildlife rehabilitation laws and regulations for the USA and Canada.  This is a huge undertaking and needs help to make it happen.  Board member, Brenda Harms is preparing a template to ensure we cover all the bases as we develop this informational database.  Are you interested in helping with the information for your State, Province, or Territory?  We can send you the template as soon as it is ready.  Or you can send Kim the email contact for your permitting office.  Any regulations or web based forms will also be of great use to your colleagues.  Not in the USA or Canada?  Send your government’s information along.  It might be a very long while before we have information available worldwide, but we can start with the countries with IWRC members!  Email information to
Don’t forget to protect yourself through these long days of hard work, never ending demands for your time and expertise, and always one more job to do.  Sleep all you need, eat well and don’t forget to laugh, maybe one of our greatest gifts for de-stressing.  I hope you can plan a break with all of us in Florida this November.  If this is not a possibility, do make time for time out, you deserve it.
My very best to you all,