A Study of Annual Reports of
Wildlife Rehabilitators for the Five Year Period 1998-2002
The complete 27 page
report, including all of the photos, tables, graphs and complied data,
is available as a pdf file and can be
downloaded by clicking here.
The information that is presented below is excerpted from the full
report, and provides an overview of the purpose and methodology of the
study, as well as a summary of some of the more significant findings.
Wildlife rehabilitators provide temporary care for injured, orphaned, or
otherwise distressed wild animals with the goal of releasing healthy
animals that can survive independently in their native environment.
While wildlife is rehabilitated in many areas and rehabilitators
maintain and review their own records, there have been relatively few
quantitative studies conducted about wider demographics and trends
related to wildlife rehabilitation.
Believing such quantitative data would be useful, we conducted a study
to quantify the demographics and caseload activity of wildlife
rehabilitators in Colorado. Annual wildlife rehabilitation records
submitted to the Colorado Division of Wildlife by each rehabilitator,
which list each animal that was admitted into rehabilitative care, were
used for this analysis. The Colorado Division of Wildlife provided this
information as a result of a Colorado Open Records Act request.
This report compiles, tabulates and analyzes the data that was reviewed
for the time period 1998 through 2002. The findings are presented
without attempting to draw subjective conclusions concerning the reason
behind certain data or trends that became evident during the analysis.
While this study
provides some useful information, it also serves to identify many
questions needing answers. We believe that only through conducting this
type of research and analysis can we as a wildlife rehabilitation
community begin to understand the many dynamics at play in our efforts
to help wild animals.
Purpose of the Study
This study was conducted in order to quantify and analyze demographics
and metrics about the wildlife rehabilitation community in Colorado.
Most previous analyses that described the nature and activity level of
state rehabilitators were based on rough estimates. This study is
intended to quantify many aspects of the community, such as caseload
statistics and release metrics, as well as provide a more in-depth and
complete view of the demographics of licensed rehabilitators.
The scope of the
study involved reviewing the Annual Species reports submitted to the
Colorado Division of Wildlife (CDOW) for the five-year time period 1998
through 2002. Submission of the Annual Species Report is a regulatory
requirement of all license holders, and is a prerequisite to the annual
renewal of the license. The report, due no later than
January 31 of each
year, indicates all activity for the past year for the rehabilitation
license holder, and contains information about each animal admitted for
rehabilitation. The content of the report is specified in regulation.
We submitted a Colorado Open Records Act (CORA) request in early summer
of 2003, in order to schedule a review of the Annual Species reports
that are maintained by the CDOW’s Special Licensing office. The CORA
request was approved by the Attorney General’s office. We reviewed the
reports at CDOW’s Colorado Spring’s regional office in two sessions in
the summer of 2003.
The data gathering was designed as a three-part process. The first step
was to review each report for certain data and counts of animals by type
or group of species, and by the animal’s final disposition.
The second step was to pick a random sample of animals from the reports
to better understand the number and types of species of animals that are
admitted for rehabilitation; their length of time in captivity; and
survivability and release rates. A laptop computer-based random number
generator program was used to select five entries from each Annual
Species Report to record on a separately designed form for such purpose.
The third step of the data gathering was to look at information for each
rehabilitator, including name, license number, city or location where
the rehabilitator was licensed, and which of the five years the
rehabilitator held the license.
The data collected was subsequently input into a series of electronic
spreadsheets for analysis. The analysis was performed in the offices of
WildAgain Wildlife Rehabilitation, Inc. in Evergreen, Colorado during
the spring of 2004.
As the data was reviewed and analyzed, five primary groupings or
categories of information emerged. These categories are as follow:
rehabilitator demographics (e.g., number, location, experience level,
2.) Animal caseload
(e.g., number of animals, species, seasonality and timing, transfers)
distribution (e.g., variation of caseload numbers between
during rehabilitation (e.g., critical first days, overall percentage of
survivors by species)
5.) Release of animals
(e.g., length of stay in captivity, release rates)
The results and findings of the study are presented using these five
A Quick Summary of
The review of 405 Annual Species reports submitted by 177 licensed
wildlife rehabilitators to the Colorado Division of Wildlife during the
time period 1998 through 2002 involving 53,000 animals indicated the
following statistics and trends:
Wildlife rehabilitator demographics in Colorado
On average, there were 106 licensed rehabilitators per year.
The net number of rehabilitators increased on average 6% per year, with
a total of 117 in 2002.
From the prior
year, non-renewals averaged 17%. New recruitment averaged 23%.
Attrition of new
license holders exceeded 20% in the first year and 50% over three years.
The median experience of 117 rehabilitators in 2002 was 4 years.
License holders were 75% female, 25% male.
Home-based facilities accounted for 95% of all license holders.
The large majority of Colorado rehabilitators were located on the more
urbanized Front Range, with 75% of the rehabilitators located 50 miles
either side of Interstate 25 from Pueblo to Ft. Collins, and with 20% on
the Western Slope.
There were about an equal percentage of rehabilitators who rehabilitated
avian species (61%) and mammal species (62%). Thirty-seven percent
rehabilitated both avian and mammal species.
The reports reviewed indicated approximately 53,000 animals were
rehabilitated statewide during the 5 years (averaging 10,600 per year).
Annual caseload statewide increased 8% per year overall (up a total of
36% from 1998 to 2002).
total of 69% of the animals rehabilitated were avian (mostly
passerines). The rehabilitated mammals totaled 28% and were mostly small
(e.g., squirrels, rabbits) to mid-sized (e.g., raccoons, fox). Two
percent of the animals rehabilitated were bats and one percent were
Most animals (80%) arrived for rehabilitation between April 1 through
September 30, with 54% of the total arriving in the 90-day period May 1
through July 31.
Rehabilitators provided an estimated 1.8 million days of patient care to
wild animals (calculated during the five year period by the average
length of stay times the number of animals).
Animal caseload distribution
Half of the rehabilitators each see 20 animals or less per year (only 2%
of total animals). Two-thirds of the rehabilitators see 50 animals or
less per year (only 7% of total animals).
Five percent of the rehabilitators each see over 500 animals per year
(66% of total animals in the state).
On average, 6% of the total number of animals each year were transferred
by and between rehabilitators for workload distribution or training
purposes, or for special expertise or caging requirements.
Survivability of animals
randomly selected sample of 949 animals (2% of total) from the Annual
Species reports were reviewed and indicated the following:
Birds died or were euthanized at twice the rate of mammals in the first
4 days of captivity.
One-third (33%) of all
birds admitted to rehabilitation died or were euthanized in the first 4
days of captivity. Sixty percent of all birds admitted eventually
One-sixth (17%) of all
mammals admitted to rehabilitation died or were euthanized in the first
4 days of captivity. Seventy-three percent of all mammals admitted
Of all animals
(all species) that died or were euthanized (33% of the sample), the
death or euthanasia occurred early in captivity (60% within the first 2
days; 80% within 5 days).
Release of animals
Just over three-fourths of all animals were in captivity less than 60
days. About 95% of all animals were in captivity 120 days or less. The
average stay was 35 days.
Less than 1% of all animals were in captivity more than the 180-day
limit mandated by Colorado rehabilitation regulations. Of these, most
were pending at year-end for continuing medical treatment, molt,
hibernation, or to be released at the appropriate time of year for the
species (e.g., migration).
In the sample analyzed, over 94% of animals listed as ‘pending’ at
year-end were eventually released.
Because a small group (only 5%) of all rehabilitators see two-thirds of
all animals in the state, overall release rates were calculated two ways
– first, based on average of all animals, and second, based on the
average release rate experienced by all rehabilitators, regardless of
their caseload size.
The average release
rate was 67% when calculated based on the average release rate
experienced by all rehabilitators, regardless of their annual caseload
The average release
rate was 52% when calculated based on all animals statewide. (This 30%
difference in average release rate was heavily influenced by the lower
percentage of animals released by rehabilitators with larger caseloads).
On average, release rates trended lower for rehabilitators with higher
annual caseloads (those with 100+ animals).
The results of this project shows
the type of data and quality of insights that can be gained from using
information submitted by rehabilitators via their annual reports to
their governing state wildlife agency. Significant information can be
gleaned from examining wildlife rehabilitator demographics and reported
caseload results over a five-year period for a single state. The same
study could easily be replicated in other states since most state
wildlife agencies require submission of an annual report containing
similar data as a condition of permit renewal. Additional studies
similar to the one presented in this report should be conducted before
suggesting meaningful trends or conclusions on a national level.
While this study reveals certain statistics and trends, it prompts many
more questions. We consider these questions as opportunities for further
research within the rehabilitation community, both at the state and
national levels. For example, the study indicates some potentially
interesting numbers concerning release rates. Since there are, however,
many factors that can influence rates of release (e.g., regulations,
policies, classifications/coding, species, age of animals), it can be
challenging to compare release rates between rehabilitation facilities
as well as between states. It will be necessary to conduct further
research into identification and assessment of release factors before
their meanings can be understood. Research and study are needed to
identify and understand the reasons for, and ways to, address the high
attrition rate of rehabilitators. It also would be helpful to look at
the reasons for a significantly higher release rate of mammals, as well
as trends in rehabilitation caseloads. And the list goes on.
In the meanwhile, we think that this type of report can be useful for
many purposes, especially if the results are applied to a specific
facility or geographic area. For instance, information could help with
planning for rehabilitation caseload, facility development, recruiting,
and purchasing of supplies. Because they indicate the overall and
beneficial impact of wildlife rehabilitation activities, these data and
statistics are potentially supportive of fundraising. They also may be
considered as input when reviewing the need for changes in the state
regulations that govern wildlife rehabilitation, as well as for
identifying training needs and when/where to offer such training.
We encourage you to
download the complete 27 page study
report as it discusses the results in much more depth, including
providing various charts, tables and graphs. If you have interest in
performing the same study for your state, region or facility,
please contact us and we can discuss more specifics as to data
collection planning and methodology.
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state regulations governing wildlife rehabilitation. Journal of Wildlife
Rehabilitation, Winter: 6-10.
Casey, Allan and S. Casey. 1995. State
regulations governing wildlife rehabilitation: A summary of best
practices. Journal of Wildlife Rehabilitation, Spring: 3-11.
Casey, Allan and S. Casey. 2000. Survey of
state regulations governing wildlife rehabilitation during 1999.
Wildlife Rehabilitation: National Wildlife Rehabilitators Association –
selected papers from the annual symposium: 173-192.
Casey, Allan and S. Casey. 2005. Survey of
state regulations governing wildlife rehabilitation: 1994-2004. National
Wildlife Rehabilitators Association, presentation at the annual