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program of reintroduction of chimpanzees of the H.E.L.P.
a few words
This program is carried out on the ground, in the Republic
of Congo, by H.E.L.P.
Congo. It began in 1996
and it concerned, at the beginning of 2006, 40 individuals, all born
in the Republic of Congo. The very great majority of them spent several years
in semi-freedom on one of the islands of the Sanctuary of Conkouati.
All these chimpanzees
were released on the site of the Triangle or near, within the
National park of Conkouati-Douli. Their release was done by
small groups, between 1996 and the beginning of 2006, after an important
medical follow-up. Since their first day in the forest, these individuals
were observed in order to study their adaptation to this new environment.
Not only the rate of survival is important, but the food
behavior of the released individuals is completely comparable with the one of
their congeneric savages. The contacts with wild chimpanzees are very
numerous and already, several of the released females gave birth to young
Thanks to those success, and rich of those experiment, the H.E.L.P.
Project study the possibility of launching a new program of reintroduciton on
another site. In addition, we propose our expertise with other projects in Africa,
interested by the handing-over in natural environment of chimpanzees.
To reintroduce chimpanzees: difficult problems!
the reintroduction of chimpanzees must face problems common
to any Re-introduction in natural environment, like:
need for respecting the
individuals concerned, the medical aspects, the wild animal populations;
the appreciation of the
interest of such an act for the species;
need for rigorous protocols
of installation and follow-up;
the taking into account
of the possible environmental impact....
Concerning the chimpanzee species, some specific
difficulties are added: the chimpanzee is a species with a very complex
social behavior. The capture of young individuals implies a serious
psychological traumatism and the loss of the social reference marks. For
this species, the training near the adults is long. The separation of the
group of origin, in particular of the mother, thus redues strongly the
capacity of living normally in forest. To try to meet the needs for the young
orphans (affection, maternal contact, training) an important direct contact
between primates and welfare source is necessary. This brings to a strong human
impregnation of these animals, potential source of problems at the time of
The introduction of new individuals in forest can
encounter important difficulties related to the aggressiveness of the
species. Indeed, it is regularly observed attacks of chimpanzees by the
congeneric resulting ones from different communities, attacks being balanced
regularly by sometimes serious wounds, even mortals.
The whole of these
factors explains in great part why there is not former cases of truths
programmes of reintroduction of chimpanzees in natural environment (see "Conservation of the species
of the program of reintroduction
its design, this program took care of the
conditions to respect, such as they are defined by
the Group of the Specialists in the Reintroductions of
the UICN. H.E.L.P. Congo particularly held account of the need for an excellent
preparation, of UN protocol
to release rigorous, of an important follow-up after the release, at the veterinary
level, behavioral and environmental impact.
ø From the very start, H.E.L.P. Congo worked in
partnership with the actors of the conservation of the zone of Conkouati, like currently the WCS
and the agents of National Forestry Commission, all in load of the management of
the National park of Conkouati-Douli.
Three essential points in this preparatory
phase: the phase of expertise, the signature of agreements with the
Congolese government, preparation on the ground
The phase of
expertises began in 1994 by a first mission from the primatologist Caroline
Tutin, who came to estimate the feasibility of this project. Following its
favourable opinion, the project was presented at the authorities and various
agreements were signed.
In 1996, a second mission of C Tutin and a mission
of the botanist P. Sita made it possible to define and study the site to
release most favorable, namely the Triangle, zone of forest with approximately 1
hour 30 of boat of the sanctuary of Conkouati.
Always in 1996, the whole of
the chimpanzees of the sanctuary were went through an important veterinary check, first
phase of the medical follow-up of this program.
Lastly, it was to install Infrastructures necessary on the site of the
Triangle: camp in forest, opening of tracks or tailboards marked out in forest
for displacements and the location.
1996 to 2001, 36 chimpanzees resulting from the Sanctuary were reintroduced
in this program. Thirty five of them had been the subject of seizure or had
been given by private individuals or Congolese zoos to H.EL.P. Congo. Only one
was born in the Sanctuary and was released, less than one year old with his
mother. These first 35 individuals were released after a rather long
passage on the sanctuary of H.E.L.P. Congo, including a stay in nursery
(of a few days to almost 3 years) and a stay on one of the islands of the Sanctuary
of Conkouati (from 3 to 8 years). On
these islands, the animals lived in semi-freedom, within socially structured
groups and the contacts with the human ones were reduced to the contribution
of additional food.
With the exception of the baby released with his mother, the individuals were
reintroduced on the site of the Triangle from 6 to 15 years old. These reintroductions
were made by small groups, from two to twelve individuals, one or two
groups being released each year, from November 1996 in mid 2001.
From September 2000 at at the beginning of
2006, four individuals, including two at the beginning of 2006, were
released on the Triangle after a stay limited on the sanctuary of Conkouati (but
always after same medical control). Resulting also from seized or donation to
H.E.L.P. Congo by private individuals, they were thus released at a youth age, one
to two years old. They are released by two and are only integrated little by
little in the groups of individuals previously released. This procedure proves
less stressing for the individual: they discovers the forest in the site
where they will live, they learns from the individuals previously slackened and they
do not undergo the stress to leave their island and to arrive on an unknown
site, after a transfer under general anaesthesia.
A particular importance was given by H.E.L.P Congo to the veterinary follow-up,
with in particular an implication of the CIRMF (International Medical
Research Center, Libreville - Gabon). The principal objective was to set up
a procedure to limit to the maximum the medical risks for the wild animal populations
present on the zone of reintroduction. To answer these requirements, H.E.L.P.
Congo maintained uninterrupted the presence of a veterinary surgeon on
his sites since 1992. Concretely, this important veterinary monitoring rests
the realization of clinical examinations, the care necessary and quarantainefor
· the realization of at least a complete
medical assessment, under general anaesthesia generally, of all the individuals
candidates for the reintroduction (clinical examination, analyses parasitic,
serologic (hepatitises, HIV...), tuberculinisation and preventive treatment
like the vermifugation and vaccination); these examents are done a second time
at the time of slackening, with the installation of a collar transmitting
and taken hairs for genetic typing
· the follow-up by remote observations
and coprologic analyses of the reintroduced animals
· the stop of the treatments of prevention
on the released animals, except at the moment of the arrival of new individuals
within already slackened groups
· the realization of veterinary acts if
the survival of a slackened chimpanzee is directly concerned.
The follow-up of the slackened
the follow-up by observations and telemetry
In their new environment, the chimpanzees equipped with transmitting collars
are the subject of a daily follow-up which becomes more spaced after
several months. In 2006, this follow-up relates to primarily the males and the
females with babies.
Thus, since December 1996, several thousands of hours of observations
were carried out. These last, based on statements separated by 10 minutes, concern
in particular: the food behavior (ex: consumed species), displacements and space
exploitation of the site of reintroduction, social interactions, contacts with
the wild populations...
The individuals are equipped the day of their release with transmitting collar
of a range of approximately a kilometer and of a lifesime of one year. In the
first times which follow their release, the chimpanzees are followed everyday,
if possible from the nest to the nest. The collars then make it possible
to locate them if they escape from such a follow-up, which is relatively current
because of the conditions of ground. With time, this monitoring is done less
intense: the collars are then essential to find the chimpanzees. The lifetime
of these collars being from approximately 1 year, are re-equipped especially
the leaders, the females with the youngest babies or the youngest ones. The
individuals without collar are then observed in a more or less occasional way,
randomly of the meetings in forest.
the genetic follow-up
Each chimpanzee concerned with our program was the subject of a genetic typing.
To know their genetic print is essential for two imperative reasons:
the animals being less
and less observed, the genetics offers to us a mean of indirect follow-up
enabling us to certify in a formal way (up to 99 %), the presence of such or
such individual at a given place and a given moment, starting from analyses
of saddles taken in forest.
the number of birth among
the females released is in permanent increase; thanks to the genetics we can
define who is the father, in particular if it is a slackened individual
or a wild chimpanzee. This is essential to understand the interactions
with the wild populations of chimpanzees.
Results for the reintroduced
Rate of survival
On the 38 chimpanzees
released between 1996 and 2002, 6 died, 4 females were lost just after their
releasing by failure of their collar, 8 individuals were followed at least three
months after their reintroduction but were not seen since more than one year,
and 21 are observed from frequently to everyday. Among the 8
individuals not seen since more than one year, we count several females having
disappeared from long periods in the past and reviews randomly of a
The nature of
the reactions of the chimpanzees slackened towards the man is one of the
most positive elements of this program. After the period of escape according to
the release, the chimpanzees generally show indifference to
the man, even if the maintenance of a neutral attitude remains essential. More
and more, they are shown even not easily accessible.
In a general way, no
contribution of food is necessary. A nourrissage was sometimes essential for
certain individuals for the period criticizes according to their slackening,
when the stress had pushed them to flee in zones not very rich in food or for a
chimpanzee convalescent. The principal causes of the interventions veterinary
surgeons are wounds, sometimes very serious, following the wild attacks of
The slackened individuals
have a food adapted behavior , rich and comparable with what is described for the wild populations and this in various plans like: techniques of collection
and consumption of the food (use of tools...), the time devoted to the food (58
% of daily time), the predominance of the fruits in the food (more than 60 % of
the time devoted to the food corresponds to the fruit consumption, especially of
pulps), food variety in term of numbers of consumed different food (more than
200), and of numbers of exploited vegetable species (more than 135), the
follow-up of the rhythms of fructifications, food exploitation known as of
reserve (sheets, stems the herbaceous ones...) in the event of fall of
availability out of fruits
Very quickly, the reintroduced chimpanzees showed a very marked exploratory
behavior. To this date, they very have widely exceeded
the framework of the
Triangle and exploit the part contiguous to the Triangle of the National park
of Conkouati-Douli. In addition, the behaviour of fusion-fission was
observed very early after the first released.
This social behavior was accentuated in 2000. It relates to the whole of the
reintroduced individuals and varies according to the number of females in heat
and the food availability, as within the wild communities.
ø Interactions with the wild chimpanzees
the interests of this program of reintroduction would be of in the long term
being able to contribute to the reinforcement of the wild populations of
chimpanzees. The contacts between wild and slackened chimpanzees are
increasingly many and durable. In the large majority of the cases, the
things are held as well as possible and the presence of observers seems to
interfere less and less. In fact the males who are more and more the victims of the
attacks of their wild congeneric, with serious wounds, having resulted in
death. On the other hand, the females are more easily accepted, especially if
they are in oestrus. They can then leave several months with them.
The very great majority
of the females were pubescent and the males in age to reproduce at the time of their release. The first birth of a baby born of a slackened female took place in
2001. We count at the beginning of 2006 a total of 8 births.
the site of reintroduction
ø No sign of overexploitation of the zone was
observed. Moreover, the chimpanzees leaving the limits of the Triangle, this
risk remains very limited.
ø the impacts of this program on the site of
reintroduction relate to especially the protection of the zone of
Conkouati. Indeed, on the forest unit exploited by the chimpanzees
reintroduced here, deforestation stopped and especially the poaching underwent a
drastic fall. This appears in particular by the increase in the contacts with
wild fauna. Thus, for example, the observations of elephants became very
frequent and those of cercopithèques almost dayly.
Results for the species chimpanzee
Results of the program of reintroduction of H.E.L.P. Congo on the level of the
species are still not very quantifiable. But we can already note that:
this action became an
essential reference for all future programs of this type; thus H.E.L.P.
Congo took part in the drafting of the new recommendations of the group of specialists
in reintroduction in the UICN. Our action makes it possible to consider new
tools for the conservation of the species chimpanzee like the reintroduction,
but also the translocation of individuals or wild populations.
this action contributes
to the protection of a single forest belt for the survival of the species:
the area of Conkouati
this action plays a considerable
part of sensitizing on becoming to it primates, as well on the level
of Congo as outwards thanks to an important effort of communication and diffusion
of the results.
Lesson and future
the phase of the release program begun in 1996 is
almost completed to date. On the other hand, the follow-up of the individuals,
even if it becomes still increasingly discrete, will continue. It is in
particular necessary to bring answers on the evolution of the social structure
of the community of slackened, on their reproductive successes and their
interactions in the environment and long term with the wild
As of now, we can say that this program is a
success, would be this only because one durable and acceptable solution was
found for the future of about thirty ex-captive chimpanzees.
Today, the H.EL.P. Project study the feasibility
of a new program of reintroduction, on another site that the Triangle.
Moreover, we propose our expertise to help of other projects wishing to develop
a program of reintroduction of chimpanzees. New adventures in prospect and
perhaps a hope for other captive chimpanzees.
But our program
also teaches that such actions are possible only by observing certain
conditions and a rigorous protocol. And that cannot be applied to all the
captive chimpanzees. Such actions can thus remain only tools. The essence of the
solution for the survival of the species chimpanzee, as for the majority of the
animal and vegetable species, always remains in the development of actions for
the protection of the in situ populations and the durable
management of their habitat. We will do our best there too!