guidelines for releasing marsican brown bear cubs into nature

GUIDELINES FOR RELEASING
MARSICAN BROWN BEAR CUBS
INTO NATURE
Compiled by Roberta Latini
with support from Leonardo Gentile and Daniela D’Amico
Ente Autonomo Parco Nazionale d’Abruzzo, Lazio e Molise
November 2015
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Acknowledgement
These guidelines have been compiled by the National Park of Abruzzo Lazio and Molise, with support from
the Institute for Environmental Protection and Research (ISPRA) and the University of Rome “Sapienza”, and
with substantial contributions from several leading experts of bear conservation:
Fernando Ballesteros Bienzobas
Fundación Oso Pardo, Spain
John Beecham
Co-Chair, IUCN-BSG HBC Expert Team
Juan Carlos Blanco
Fundación Oso Pardo, Spain
Claudio Groff
Provincia Autonoma di Trento
Marko Jonozovic
Director Forest Service Slovenia
Mark Haroldson
Supervisory Wildlife Biologist, U.S. Geological Survey, Northern Rocky
Mountain Science Center, Interagency Grizzly Bear Study Team
John Hechtel
International Association for Bear Research and Management
Đuro Huber
Professor at the University of Zagreb, Veterinary Faculty, Department of
Biology Co-Chair of the IUCN European Brown Bear Expert Team
Alexandros Karamanlidis
ARCTUROS, Civil Society for the Protection and Management of Wildlife
and the Natural Environment
Ilpo Kojola
Finnish Game and Fisheries Research Institute, Finland
Guillermo Palomero
Fundación Oso Pardo, Spain
Pierre-Yves Quenette
Office National pour la Chasse et la Faune Sauvage, France
Georg Rauer
Veterinary University of Wien, Austria
Jon Swenson
Professor at the Norwegian University of Life Sciences, Department of
Ecology and Natural Resource Management, Co-Chair of the IUCN
European Brown Bear Expert Team
The National Park of Abruzzo Lazio and Molise wishes to thank Dr. Piero Genovesi of ISPRA, Prof. Luigi Boitani
of the University of Rome “Sapienza” and all the experts who contributed to the drafting of this document.
Thanks to Rosie Trachman for your continued support in translating.
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To John Beecham
who has always supported and guided us with his
professionality, expertise and friendship.
If Morena will have a chance, it will be thanks to him!
To little Morena
who has helped us grow professionally, with the hope
that this experience proves to be a small contribution
to the conservation of our Marsican brown bear.
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1.
Foreword
A Marsican brown bear cub of this year was found on the 22nd of May, 2015 in the area near Villavallelonga
(AQ), inside the borders of the Abruzzo Lazio and Molise National Park. This event made it necessary to make
a number of complex decisions about the animal's future. Multiple factors were taken into account when
deciding whether to attempt to take the cub into captivity: including decisions taken by the park staff in this
emergency situation. Some of these factors were, the highly anthropic nature of the area where the cub was
found, the cub's age and physical condition, management of public opinion which was already aware of the
cub's existence, and an understanding of the importance that each single Marsican Brown Bear has in a
subspecies which is at risk of extinction.
International experience in the field of rehabilitation and release in the wild of bear cubs is vast and
diversified with some examples that were not successful (Huber et al. 1994, Huber 2010). However in other
cases there appears to be a high level of success (Beecham et al. 2015).
The experience of taking in this cub represents a challenge for the Abruzzo Lazio and Molise National Park
(PNALM), considering the technical difficulties and multiple unknowns, (this is the first experience of cub
rehabilitation with a Marsican brown bear), but it also represents an opportunity for communication, and for
the conservation of this subspecies.
2.
Why placing a Marsican brown bear cub for recovery in captivity.
The conservation of the Marsican brown bear is one of the most important challenges for the Italian and
European wildlife, and it is without a doubt one of the most important goals of the Abruzzo Lazio and Molise
National Park.
The Marsican brown bear is a subspecies which has a high risk of extinction, its numerical consistency,
although stable in the past years, was estimated in 2014 as 50 bears (IF 95%: 45 – 69 bears) which is below
the minimum threshold for long term survival, especially considering the limited number of females currently
present (Ciucci et al 2015). The extremely low genetic variability further compromises the survival of the
species, as it increases the risk of inbreeding depression. Mortality of anthropic origin, which is still very high,
represents the main threat to the longevity of the population. Because of the many causes of mortality, a
demographic increase seems possible only on the condition of a systematic reduction of mortality of
individuals, particularly adult females. (AA.VV. 2011).
It is evident from these considerations that each single Marsican brown bear individual is extremely valuable
for the conservation of the species, especially if it is a female. A program which releases found cubs back into
nature could contribute both directly and indirectly to the conservation of the population. In addition, this
type of program helps to maintain genetic diversity in small isolated populations (Jamieson et al. 2006).
These projects also have a strong positive effect on public opinion, and can favor the backing and
participation of the public for other conservation projects. (Seddon et al. 2012).
Additionally, this experience can play an experimental role which can be useful for the management of similar
cases that may come up in the future.
3.
International experience in releasing orphan cubs in nature.
In the past, the management of orphan cubs had always been geared towards their recovery for a life in
captivity, or in some cases, euthanasia. The successes which have been obtained in recent years in different
international realities are encouraging and help to guide programs for the reintroduction in nature of orphan
cubs (Kelly et al. 2010), mostly because it has a strong impact on the public (Beecham, 2015). Recovery of
wild fauna in nature happens regularly for birds (Golightly et al. 2002), marine mammals (Moore et al. 2007)
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and primates (Agoramoorthy and Hsu 1999). When dealing with bears, the major concerns of experts
(Herrero 2005) are about the level of habituation that bears who were released after being raised in captivity
might have towards humans, undermining, in a case of failure, the efforts of the captive raising program, and
causing potentially very negative consequences on the support of the public opinion towards the
conservation program.
The first release into nature with a particularly protected species happened with the panda in china in 2006,
whereas the first brown bear release was in 1975 in Montana, in the USA. In the last 30 years there have
been numerous experiences of recovering cubs in Croatia, Romania, Spain, Greece, Russia, South Korea,
Indonesia, Canada and the United States (Beecham 2006).
Brown bear cubs depend on their mother for their first 17-29 months of life (Camarra 1989; McLellan 1994 ),
whereas with Marsican Brown Bears, it has been verified that this separation happens relatively early, after
17 months of age (AA.VV., 2011); In this period the cubs are subject to a high risk of natural mortality, and
that this risk increases if the cubs are orphaned.
European literature about survival rates of orphaned cubs (Huber, 2005, Palomero et al. 1997; Pazhetnov ,
2005; Swenson et al. 1998) indicate that starting from six months of age (between 5 and 7) the survival rates
of orphan cubs doesn’t seem to be significantly different from that of cubs who are accompanied by their
mother, whereas the survival rates of cubs who lose their mothers before the 3° month of age, present very
low survival rates, both because they depend greatly on mother’s milk, and because of possible aggression by
adult male bears. Up to this point, information regarding techniques for raising cubs, release methods and
post release monitoring, had been very fragmentary and inconsistent. This made it difficult to evaluate the
success of these projects.
In a recent article, Beecham and other authors (2015) gathered and examined all of the experiences
documented from 1991 to 2012 in different contexts in North America, Europe, and Asia. In particular, they
evaluated the management possibilities and the conservation implications of reintroducing captive raised
bears back into nature. They analyzed post-release survival rates, causes of mortality, conflict situations with
anthropic activity, movements and reproduction in a sample of 550 bears of brown bear, American Black Bear,
and Asiatic bear species in 12 captive raising programs throughout the world.
The results of this study are quite reassuring, they indicate that there are no statistical differences in survival
rates among the different species. these survival rates range form 0,50-1,00 and the principle causes of
mortality of cubs raised in captivity and then released did not differ from those in nature. the logistic
regression model indicates that for the American brown bear, mortality rates for cubs orphaned before 8
months of age are lower in individuals released at higher weights. Although many professionals showed
concern about the possibility of higher levels of conflict with anthropic activities for cubs raised in captivity
particularly if they are offspring of mothers who demonstrate problem behaviors, 94% of released bears did
not demonstrate such behaviors. Even though there is still not a lot of documentation on the subject,
captivity, if managed correctly, doesn't seem to increase the onset of problem behaviors in cubs. Beecham et
al (2015) suggest that releasing cubs with a higher weight and in less anthropic areas for at least the first
period, should further reduce this risk.
Of bears for whom long term post-release monitoring was possible, it was possible to document 8 of 10 bears
released in New Jersey and 6 of the 10 released in South Korea, respectively they produced 28 cubs in 11
litters and 10 cubs in 7 reproductive events (Beecham et al , 2015). In particular, it emerged that the age of
the first reproduction didn't deviate from what has been documented for bears who have always lived in
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nature (Garshelis, 1994; Yamanaka et al. 2011) and that reproducing females who were raised in captivity
were not excluded from the best habitats.
In Spain, between 2008 and 2014, five orphaned, abandoned or injured bear cubs an one yearling have been
found in Spain and have been rehabilitated in captivity in order to be released in the wild. All of them were
females, four from the Cantabrian Mountains and one from the Pyrenees. In three cases the bears were
injured -two of them seriously injured- when they were found, and all of them recovered after veterinary
treatment. Three of the five bears were released in the field (the yearling in August and two cubs in
November); in two cases, they did very well in the wild, and in the third case (Molina) the cub had to be
recaptured because she was habituated to humans. Molina was found very seriously injured and she received
an intense veterinary treatment for two weeks. Maybe the close contact with people during this treatment
caused her habituation. The two other bears died before her release. One of them died of capture myopathy
in the transport vehicle a few minutes before being released; the second cub died a few days before her
release as a result of the surgery to implant an intraperitoneal VHF radio transmitter for her monitoring
(Palomero, Blanco, Ballesteros, pers. comm.)
In Italy, the only experience which is comparable with that of the cub “Morena” of the Abruzzo Lazio and
Molise National Park, is that of the cub from Trentino "M11" who, after 38 days in captivity, seems to have
shown good short-term post-release survival, but the animal in the following year showed behaviors, such as
predation on the outskirts of villages for example, and the extreme habituation towards people, brought the
competent authorities to authorize the removal of the individual (Groff 2014)
In Spain, between 2008 and 2013 there have been 4 cases of raising and releasing orphan cubs, one female
who was recovered in June and released in November, and a 16 month old female who was found injured in
April, treated, and successfully released in August. Neither of these cubs showed signs of habituation, and
they both went on to lead a natural life.
Work was done on two other cases in Spain, but the failure on this occasion was caused by the unsatisfactory
physical condition of the animals: one cub died in captivity, whereas the other, who was recovered in
September weighing only 6 kg, was released in November but recaptured after a short time because,
probably due to the animal's low weight and other health problems, it frequented towns. Palomero and the
other authors are in agreement that in this case, the lack of success was likely due to the unsatisfactory
physical conditions of the cub (Palomero, pers. comm.).
In Greece, the experience is from 3 cases, two males who were successfully raised and released in the winter
together, and a female who was released in the winter but died some months later. In this last case, it was
not possible to immediately examine the carcass in order to determine the cause of death.
In conclusion, captivity of bear cubs is considered by many authors as a possible cause of habituation to
humans, with the consequent risks both to the mid-long term survival of the animal, and the increase of
conflict situations (Huber 1994, Clark et al 2002). Despite this, an analysis of the data regarding multiple bear
species in different geographical and environmental contexts seems to indicate that in many cases, the
carefully planned rehabilitation of individuals may mitigate some of these risks. It is necessary in any case,
that the behavior of the animals, both while in captivity and after there release, be carefully monitored for a
mid length period of time. This is important in order to make it possible to intervene promptly in the case of
problem situations between the bear and human populations.
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For the elaboration of these guidelines, reference was taken from the WSPA guidelines (Beecham 2006) those
elaborated for Greece (Beecham 2009) and from gathered and documented international experience, which
was put together after an international conference in Russia in 2007 (Beecham 2007).
4. Release
There are multiple factors which must be considered in order to decide the site and time of the release,
elements which are strictly connected to each other. To begin with, it is necessary to reduce as much as
possible the time of captivity of the cub in order to minimize the risk of its habituation to people.
Some rehabilitation programs call for the cub's release as early as possible, in late summer or the beginning
of the fall when large quantities of food are present in nature. Some researchers (Beecham 2006) on the
other hand, suggest that the best release period coincides with the period that the cub would separate from
it's mother in nature, in the spring of the following year. This strategy should maximize the likelihood of the
cub's survival (Beecham 2006, Beecham, 2011). In this specific case, because Marsican brown bears are
smaller than European brown bears, it is believed after a careful comparison between weights of animals
immobilized both in nature and captivity, that the cub should weigh at least 35 kg at the time of release. In
any case, the general physical conditions of the cub will be evaluated, with particular attention paid to
whether the cub has sufficient fat reserves to survive the winter.
It is essential that at the moment of release, the cub's weight is much higher than that of a cub of the same
age in nature, in order to prevent the cub from adopting problematic behaviors once released in an
environment which he is unfamiliar with and above all, to reduce the risk of predation by other bears.
(Beecham, 2006, Beecham, 2011).
In any case, independently of the choices which will be taken, around a month before the release the cub
should be immobilized to:
measure the circumference of the neck, in order to see the size for a collar;
effect treatments that will avoid the contamination and diffusion of pathogens, including
those of a parasitic nature post-release into the release area;
take serological samples and swabs in order to evaluate the bear's health.
The results of the laboratory tests will be used to make decisions about the release.
If possible, the cub will be fit with a "training" collar for a week or more before the release, as this could help
get the animal used to wearing a collar before she is released (Mark Haroldson, pers. comm.).
4.1 Release sites and periods
Certain elements will have to be taken into consideration when deciding about the release site:
the availability of water and adequate trophic resources
potential denning sites
low human densities
low bear densities
distance from towns and anthropic activity (agriculture, livestock, hunting)
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Among these factors, the one which is doubtlessly the most important is that the release happens in a quiet
site with a low probability that that the cub will meet people, for at least the first two weeks after release.
(Beecham, 2009).
In the specific case of the cub Morena, the decision about the date and site of release depends essentially on
how much weight she is able to gain in this period, and the behaviors that she displays during her time in
captivity.
The criteria for the choice of the date and site of release were the subject of consultation among various
national and international bear experts.
4.1.1 Time of release
Cubs are usually released at the beginning of autumn, in the winter, or in spring, as described in the
guidelines (Beecham 2006; Beecham 2011). According to Beecham's experience (pers. comm.) there are no
significant differences between the winter and spring release options particularly when it comes to survival
rates and habituation. From the park's point of view however, there are advantages and disadvantages,
specifically on a technical level. These considerations were carefully evaluated, the considerations are as
follows.
Late summer or early autumn release: although the bear would have the advantage of being released in a
period with abundant trophic resources, there are too many issues in a territory such as that of PNALM :
a) A higher probability of contact with people, because there is still a lot of anthropic activity happening
in this period
b) hunting activity in the area of external protection
c) higher risks of mortality tied to conspecific predation and conflict with human activity.
For these reasons, this possibility isn't being considered.
Winter release: the main advantage of a winter release is that at the end of the denning period, the cub has
a long period of calm in order to adapt to the new environment before anthropic activities significantly
increase. Cubs have an innate instinct which permits them to know where, how and when to choose and
prepare a winter den.
a)
Deep winter release (January – early February) this technique gives us multiple technical difficulties,
and needs specific prerequisites such as:
-
finding a area where a known preexisting natural den already exists, or building an artificial den;
inducing hibernation
transport to the natural or artificial den
homogeneous snow cover with a depth of at least 30 cm, so as to discourage the abandonment of
the den after release (Beecham, 2006; Beecham 2011).
This method is not considered appropriate, both because it entails many technical difficulties and
because of problems in predicting the weather conditions which would be necessary for this kind of
release.
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a)
Early winter release (November-early December) this method is simpler than the mid winter release
option, although both of these options are more complicated than a spring release. At the present time, the
early winter seems to be the best time for Morena's release. This option would reduce the time that she
would spend in captivity, reduce the technical difficulties tied to predisposing a den, the cub would be large
enough to defend herself from predators and would have the necessary time to find a suitable denning site.
In addition, this release option would not be conditioned by the snow cover.
This method seems to present a more moderate risk of being unsuccessful.
Spring release: A spring release would coincide with the natural time of separation of family groups, food
resources would be abundant and have high protein contents. There would still be reduced anthropic activity
which would give the cub the initial period of calm necessary to become familiar with her new environment.
Although most of the sites used by Marsican brown bears in the spring are in lower valley areas which are
close to roads and at lower elevations (Latini, pers. comm.).
Spring releases are logistically simple but have the disadvantage that the cub has to be kept in captivity over
the winter period.
In this case, the induction of hibernation in captivity would have to be planned. This would be done by
interrupting the bear's feeding starting from the middle of November. With the induction of hibernation, the
bear's contact with people would be reduced despite the longer period of time that she would spend in
captivity.
This option would involve keeping the bear in captivity for a longer period of time. However it still seems to
be characterized by a high probability of success.
To summarize, in the cub Morena's specific case, a winter release is being planned. If the
cub's conditions are not favorable (weight lower than 35 kg, or health problems) a spring
release after a denning period in captivity will be chosen.
4.1.2 Release area
The release area is tightly connected to the release period, due to environmental characteristics that change
over the seasons: in the winter, a denning site would be needed, whereas in the spring, food resources would
be necessary. A visit and evaluation of possible release sites was done together with Doctor Beecham. It was
decided, based on knowledge of the territory and the known difficulties, that the release should take place at
the heart of the PNALM territory. The option of choosing a release site in the Majella National Park was
evaluated. However this hypothesis was discarded after discussions between professionals from both parks
because of the delicateness and experimental nature of the operation. The Majella Territory didn't offer the
necessary conditions.
In terms of transport options for the release, both the possibility of ground transport (with automobiles or on
foot) and that of helicopter use are considered.
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5. Post release monitoring
The goals of the post release monitoring after the cub's release in nature will be:
1) to verify the movements and survival probability of the released cub. This is important in order to permit a
timely intervention if it proves necessary.
2) to determine eventual cases of conflict situations with anthropic activity, in order to be able to intervene
with maximum speed with an attempt to dissuade the animal or possibly decide on the use of other forms of
intervention.
For this reason, the bear will be fitted with Ear tags for being able to recognize the cub from a distance and
a satellite collar with the following characteristics:
- a drop-off mechanism with a timer and modified band (cut and re-sewed) in case the drop-off doesn't work;
- a signal of activity and mortality;
- VHF reception active 24h;
For the first month post-release, the telemetry activity relating to survival (daily checking for a signal of
mortality and activity) and to movements will be more intense (one localization every 3 hours) and will be
reduced to one localization a day during hibernation.
In order to reduce the disturbance caused by the park staff, there will be no site visits performed in the
winter months. The area will only be visited in the case that the localizations aren't received. From 4 months
after the release , from hibernation, and until the following denning period, a program of one fix/7 hours will
be programmed, with the exception of a period of around 7 days per month when 1 fix/hour will be sent in
order to permit aimed visits, for finding scats and prints in rest and feeding sites.
As suggested from the experience in Trentino, it is important that the telemetry activity should not interfere
at all with the bear. For this reason, it is fundamental that the telemetry activity be conducted by a small
group of motivated and knowledgeable people in order to prevent sensitive information such as the bear's
localization and movements from being published thereby permitting people to observe the bear without
reason.
Although there is frequent presence of the Marsican Brown Bear both inside or on the periphery of towns,
specifically in particular seasons of the year for example in the late summer, as soon as the telemetry data
indicates the presence of the cub in the area of a town, the methods of dissuasion which are discussed in the
“Protocollo operativo per la prevenzione e la gestione del fenomeno degli orsi confidenti e/o problematici”
will be applied starting from the first day of noted presence.
In October of 2016, before the winter and the collar's automatic drop off, the bear will be newly immobilized
in order to substitute the radiocollar and continue with long term monitoring. The Abruzzo Lazio and Molise
National Park has much experience with immobilizing bears in nature: between 2004 and 2015 the park has
performed 47 immobilizations in nature without registering any problems. Considering the exceptional and
experimental nature of this event, the continuation of the long term telemetric monitoring after release is
believed to be fundamental, in order to acquire data about the bear's survival, movements, use and selection
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of habitat, timely recovery of an eventual carcass to determine the cause of mortality, and to verify the
occurrence of any problem behaviors.
If the monitoring should show a situation of extreme conflicts with anthropic activity, frequent or severe
problem behaviors by the bear, or serious physical conditions of the animal, the hypothesis of immobilization
in order to put the animal in permanent captivity will be taken into consideration.
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