BCB 341: Principles of
Conservation Biology
EX SITU CONSERVATION
Lecturer: James Reeler
Material by: Sam Hopkins
INTRODUCTION TO EX-SITU CONSERVATION

Involves taking an animal or plant out of its
habitat and placing it in human care

This term covers old methods such as zoos, as
well as new methods such as seed banks and
gene banks

Ex-situ conservation may not be the ideal method
but often the only answer
THE CONVENTION ON BIOLOGICAL DIVERSITY 1

1992- a meeting of world leaders took place at the
UN conference on environment and development

The convention on biological diversity was
signed by over 150 countries

In this convention a whole article was set aside
for ex-situ conservation (article 9)

This was supposed to complement the in-situ
strategies already discussed in the convention
ARTICLE NINE OF THE CONVENTION OF BIOLOGICAL
DIVERSITY 1

Adopt measures for the ex-situ conservation of components of
biological diversity, preferably in the country of origin of such
components

Establish and maintain facilities of ex-situ conservation and
research on plants, animals and micro-organisms, preferably in
the country of origin of genetic resources

Adopt measures for the recovery and rehabilitation of threatened
species and for their re-introduction into the natural habitats
under appropriate conditions

Regulate and manage collection of biological resources from
natural habitats for ex-situ conservation purposes so as not to
threaten ecosystems and in-situ populations of species, except
where special temporary ex-situ measures are required

Co-operate in providing financial and other support for ex-situ
conservation facilities in developing countries
THE THREE SIDES TO EX-SITU
CONSERVATION

Zoos, parks and botanical gardens

Seed banks

Gene banks
THE HISTORY OF ZOOS

The emperor Wen- Wang constructed a 600
hectare ‘Garden of intelligence’ in the 12th
Century BC 2

Animal collections are known from Saqqarah in
Egypt in 4500bp

Alexander the great kept tigers and parrots in his
court 2

The Romans took many animals out of the wild
for their amphitheater antics 2
THE HISTORY OF ZOOS
London zoo in Regents Park was opened on 27th
of April 1828 2
www.shoarms.com/zootails


These zoos were
pleasure gardens for
the rich
www.shoarms.com/zootails
THE HISTORY OF ZOOS
THE HISTORY OF ZOOS

Little changed until the 1960s when the public
started to become aware

There are now over 1000 organised zoo houses in
the world with around 1 million animals housed 4
www.petsyclopedia.com
GERALD DURRELL

Started life as an animal collector for other
zoos

He established Jersey zoo which opened in
1959 and introduced the idea that zoos should be used to
conserve, he believed that zoos had a responsibility to save
animals from extinction

He pioneered inter-zoo exchange swapping information and
animals

“There are only two ways to find out about how an animal lives,
and what its habits are: one is to study it in the wilds and the other
is to keep it in captivity. As the greater proportion of zoologists
cannot go to outlandish parts of the world to study their
specimens in the field, the specimens must be brought them.”
Gerald Durrell (1953) The Overloaded Ark.
THE AIMS OF ZOOS

The main aim of a zoo is to house whole animals
for breeding and re-introduction

A secondary aim is to educate the public

The world zoos conservation strategy
estimates that there are 1100 zoos in the world
and they receive over 600 million visitors
annually 4
THE WORLD ZOO CONSERVATION STRATEGY; THE ROLE OF THE
ZOOS AND AQUARIA OF THE WORLD IN GLOBAL
CONSERVATION 4

A paper was written by a collaboration between the IUDZG,
CBSC, IUCN and SSC

It was meant to set out the future for zoos

The ultimate goal is that in the future zoo collections will be
co-coordinated globally

But for now they look to base zoo collections on
conservation objectives

Suggesting that ex-situ zoo populations should be
managed so as to support the survival of species in the
wild
THE WORLD ZOO CONSERVATION STRATEGY; THE ROLE OF THE ZOOS
AND AQUARIA OF THE WORLD IN GLOBAL CONSERVATION 4

This paper suggests that genetic degeneration and domestication
can be minimised by co-operatively managing zoo populations

Guidelines are set out to try to maintain as much genetic
variability as possible and when this is carried out properly these
populations can serve as genetic reservoirs for species survival in
the wild

There are a few ways of maintaining genetic diversity. Many zoos
keep stud books or use population management software and
animal record databases e.g. ARKS or ISIS

A population of 250 to 500 individuals is required to maintain
genetic variability for at least 100 years

Ex-situ conservation will not work for all species so subjects must
be carefully chosen. Zoos must be able to maintain and breed the
species and species must raise public awareness
THE WORLD ZOO CONSERVATION STRATEGY; THE ROLE OF THE
ZOOS AND AQUARIA OF THE WORLD IN GLOBAL
CONSERVATION 4

On top of keeping endangered species alive and genetically
diverse zoos also have an important role to play in research

This research is relevant to in-situ conservation

Zoo knowledge on the biology of small populations will
become increasingly relevant to conservation of wild
species when natural habitats are reduced and species
ranges are fragmented
The first deliberate use of
a zoo was to prevent
extinction of the Arabian
Oryx

These animals were
hunted by the Bedouin as
a test of manhood

When spears were
swapped for machine guns
the numbers declined
www.phoenixzoo.org

www.omanet.om/english/tourism/wildlife/images
ZOO SUCCESSES – THE ARABIAN ORYX
ZOO SUCCESSES – THE ARABIAN ORYX

The last wild animals were shot in 1972

15 individuals were in a zoo in Phoenix, Arizona

The first six calves were male but in 1966 a
female was born

By 1977 there were 60 individuals in the herd

Now they are found in zoos around the world and
are being re-introduced in Oman
ZOO SUCCESSES- THE CALIFORNIAN CONDOR 2

The Californian Condor fed on
carrion of bison

When bison numbers declined
(killed to starve the Native Americans) so did the condor
numbers

In the mid 1980s there were 5 birds in the wild and 24 in
zoos

In 1992 the zoo population had increased to over 60
individuals

Now the birds are being re-introduced

Some of the introductions have been successful, others not
so. If the animals get into urban areas they tend to hit
power lines and drink anti-freeze
OTHER ZOO SUCCESSES 2

Peter Davids Deer

Przewalskis wild horse

Mauritius kestrel

Hawaiian goose

European bison
KEEPING GENETIC DIVERSITY

As has been discussed before, it is
important to keep genetic variation in
these small zoo populations

In the cases of the Arabian Oryx and the
Californian Condor the last remaining
animals were taken from the wild to
preserve genetic diversity
KEEPING GENETIC DIVERSITY- THE CHEETAH

An oddity is the Cheetah Acinonyx
jubatus. This cat lacks retractable
claws, fertility is low, infant mortality
is high and keepers find it less intelligent than
other big cats

Tests looked at variation of 52 enzymes and
found none

DNA analysis suggests that 10,000 ybp the
cheetah population was down to one female and
one cub
THE QUAGGA 5

The Quagga inhabited the Karoo and the
State and became extinct in 1883.
hunted to extinction, not for meat
because it competed with livestock
Free
It was
but

Suggested that it is a sub-species of
the plains Zebra

Looking at the most resent genetic work it diverged from
the plains zebra 120,000- 290,000ybp 6

Quagga project established in 1987.

Attempting to breed a Quagga through selecting plains
Zebras with Quagga traits

Suggest that these animals could be called Quaggas as
they are determined though coat characteristics
BOTANICAL GARDENS

There are estimated to be around 1600 botanical
gardens throughout the world and these receive
over 150 million visitors a year 2

The Botanic Gardens Conservation Institute
(BGCI) was set up in 1987 and its role is to collect
and make available information on plant
conservation 2

These botanical gardens are important as it is
estimated that 60,000 plant species could be lost
in the next 50 years 2
BOTANICAL GARDENS

Botanical gardens tend to look after plants in one
of the five categories below 2

Rare and endangered

Economically important

Species that are needed for the restoration of
an ecosystem

Keystone species

Taxonomically isolated species
BOTANICAL GARDENS

Selecting these species is hard and a number of
factors must be taken into consideration 2

Extinction risk

Suitability of plant for ex-situ conservation

Value of plant

Ease of collection

Funds available

Chances of success
BOTANICAL GARDENS – PLANT REINTRODUCTIONS 2

In some ways plant re-introductions are easier
than animal e.g. easy to monitor as plants don’t
move

In others, it is harder because if the wrong site is
selected then the plant cant get up and move

When re-introducing it must be decided on
whether seeds, seedlings or adults are going to
be replaced, each has their pros and cons
BOTANICAL GARDENS 2

Another type of botanical gardens are like
plantations

They provide a safe place for plants that do not
take well to seed banks

Problems include;

The risk of disease like any mono-culture

Take up space

Less genetic diversity than normal seed banks

Vulnerable to environmental disaster
BOTANICAL GARDENS SUCCESSES –
MALHEUR WIRE LETTUCE 7

In the 1970s there were about 750
individuals of the Malheur wire lettuce
(Stephanomeria malheurensis) in the
wild

Thankfully, Dr L Gottlieb collected seeds from all
portions of the population in the 1970s

After a fire in 1972 an exotic called
cheat grass (Bromus tectorum)
took over

By 1985 the wire lettuce was extinct
in the wild
BOTANICAL GARDENS SUCCESSES –
MALHEUR WIRE LETTUCE 7

The collected stock was maintained

Re-introductions took place

In some plots where the lettuce was re-introduced
the cheat grass was removed

In the first year 40,000 seeds were produced

Plots with cheat grass remaining yielded smaller
and less quick to flower plants

Now numbers fluctuate due to cheat grass,
mammals, rainfall etc
BOTANICAL GARDENS SUCCESSES –
TORREY PINE 7
In 1988 there
were only 400 to
500 individuals
of the Torrey
pine (Pinus
torreyana) in the
wild
www.blueplanetbiomes.org/torreypine

The Torrey pine




In 1989 there was an
outbreak of Ips beetles
(Ips paraconfusus)
Ips paraconfusus
www.blueplanetbiomes.org/torreypine
BOTANICAL GARDENS SUCCESSES –
TORREY PINE 7
By 1991, 840 trees had died due to the Ips beetle
30,000 seeds from 149 trees were collected
Before the trees could be re-introduced the Ips
beetles had to be exterminated
BOTANICAL GARDENS SUCCESSES –
TORREY PINE 7

In the first 6 months of 1991, 280,000 Ips beetles
were caught in funnel traps and the Ips were
eliminated by 1992

In 1992 trees were returned

Returning progeny to correct area genetically

Seeds only had a 2% germination rate

Container grown seedlings did well

Now there are 6000 individuals in the wild
BOTANICAL GARDENS FAILURES –
SOPHORO TOROMIRO 7

The last wild individual died in 1960

There have been 13 unsuccessful reintroductions between 1965 and 1994

Trees are kept in botanical gardens in New
Zealand, Australia, Chile and Europe but they are
probably all from the same parent
SEED BANKS 8

Seed banks allow the storage of genetic diversity
of whole plant populations

Preserving the seeds for use later is a long
process, it involves;

Cleaning

X-ray analysis

Drying, packaging and storage

Germination monitoring
SEED BANKS – CLEANING 8

Occasionally clean seed is collected in the
field

More often seed is collected still in its fruit

Seed must be taken from the fruit
undamaged

This reduces bulk and disease risk

Seeds are often liberated by hand
SEED BANKS – X-RAY ANALYSIS 8

A few seeds are taken and X-rayed

This is done to see how many of the
sample are empty seeds and find any
insect larvae hiding in the seeds

The X-rayed seeds are often thrown away
afterwards as they may be genetically
damaged
SEED BANKS – DRYING, PACKAGING AND
STORAGE 8

Drying and freezing the seed increases the
time that the seed will last

Seeds are dried in cool conditions (1518°C) with the relative humidity at 11-15%

This takes about a month

The seed is then put into an airtight
container and kept at -20 °C
SEED BANKS – GERMINATION MONITORING
8

A few seeds are tested for viability once
they have been frozen

If they do not germinate they are either
dead or dormant, to distinguish between
the two states the vital stain Tetrazolium is
used

A few seeds are tested every ten years to
check germination
SEED BANKS –
THE MILLENNIUM SEED BANK PROJECT 8

Global conservation program

Linked to Kew gardens

Aims of the project are;

Conserve 10% (24,000 spp) of the worlds seed baring flora by
2010

Conserve all the seed baring flora in the UK by 2000

Research into seed conservation

Allow seeds to be used in research elsewhere

Make seeds available for re-introduction

Assist in plant conservation globally

Public education
SEED BANKS –
THE MILLENNIUM SEED BANK PROJECT
8

So far the project has managed to secure most of
the UKs native flowering plants

Collaborations have been formed with 16 other
countries

As well as conserving seeds these collaborations
are helping to prioritise species to conserve,
research into local plants and train local people

Each of these collaborations are different
depending on the country e.g. Kenyan seed for
life, USA seeds for success
SEED BANKS – THE MILLENNIUM SEED BANK PROJECT IN
SOUTH AFRICA 8

Collaboration with National Botanical Institute started 2000

Aim to conserve SAs flora by creating seed collections that
are well documented concentrating on threatened and
endemic spp

exciting discoveries;




Brachystegia spiciformis has been found in a
Miombo woodland in Soutpansberg, 20m tree
that has been undetected until now
Rediscovery of Dioscorea elephantipes (Elephants foot yam)
Rediscovery of the last remaining population of
Cylindrophyllum hallii
2 MSC projects investigating germplasm storage of the
medicinal plants of the family Amaryllidaceae
GENE BANKS

Gene banks are somewhat like seed banks

Eggs, sperm and embryos are
cryogenically frozen to protect the genetic
variation of a species

The zoological society of San Diego has
developed a frozen zoo
GENE BANKS – THE FROZEN ZOO 9

It is housed by the Zoological Society of San Diego and is
one of the worlds largest collections

The frozen zoo is meant to provide materials to aid species
recovery and population viability they also bank cells from
species that are close to extinction

Holds frozen skin cells, DNA, RNA , semen, embryos,
oocytes, ova, blood and frozen tissue

They hold the genetic material from 500 Przewalskis
horses, 150 western lowland gorillas, 80 black rhinos, 22
Queensland Koalas and 19 Bornean bearded pigs

These are all available for scientific study
GENE BANKS – THE FROZEN ZOO 9

Most recently cells from a Hawaiian
honeycreeper called a po’ouli

The species is now extinct in the wild

Cell harvesting is not a way that the bird can be “brought
back to life” but more a way that research can be carried
out on their DNA

"Even though the genetic program of the po'ouli may be preserved
through cell cultures, the DNA will not tell us what it's song was or allow
but a most primitive view of the living organism in its environment, yet, we
save all that we can, trust that those in the future will be glad for our
efforts, and hope that efforts for other species can be undertaken to
forestall the necessity to save a few precious cells as the legacy of a
unique species." Oliver Ryder Ph.D., geneticist for the San Diego Zoo's
department of Conservation and Research for Endangered Species
THE PROBLEMS WITH EX-SITU
CONSERVATION

Captive and wild populations diverge genetically 2

Interbreeding 2

Hybridisation 2

In the case of gene banks, living populations are necessary
to pass on non-genetic learned behaviours 9

Ex-situ tends to only save particular species whereas in
situ saves whole ecosystems 10

Impossible to conserve whales! 11
THE BENEFITS OF EX-SITU CONSERVATION

With only 3% of land in nature reserves world wide often
the only answer 10

“No large wild terrestrial animal will persist long into the future unless
cared for in some way by man. There will be insufficient habitat for most
large species and protected habitats will be in pieces too small or too
unstable to sustain viable populations of the plants and animals they seek
to protect. For these and other reasons conservation biologists will be
forced to depend more and more on ex-situ care and biotechnology to
help protect diversity at both species and genetic levels” William Conway,
New York Zoological Society taken from In Ecology, Change brings
stability (1986) Science 234:1071-1073

Botanical gardens can help in ethno biology strengthening
collections that have traditional and cultural implications 2

Re-introductions have occurred for at least 120 animal
species and 15 of these are definitely established in the
wild and are now self sufficient populations 4
REFERENCES
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1. Convention on biological diversity http://www.biodiv.org/convention
2. Worley, D., (1996) Ex situ conservation. Chapter in Conservation biology ed
Spellerberg, I. Pp 186-201
3. www.wta.org.za/info/history/zoos.htm
4. World Zoo conservation strategy. IUDZG/ CBSC/ IUCN/ SSC (1993). Executive
summary, the world zoological conservation strategy; the role of the zoo and aquaria
of the world in global conservation
5. www.quaggaproject.org
6. Leonard et al. (2005). A repid loss of stripes: the evolutionary history of the extinct
Quagga. Biological Letters 1: 291-295
7. Conservation Biology for the coming decade (2ed) (1998). Eds Fielder, P. L. and
Kareiva, P. M.
8. http://www.kew.org/msbp
9. www.cres.sandiegozoo.org/projects/grfrozenzoo.html
10. Soule, M. E. (1991). Conservation tactics for a constant crisis. Science 253:744750.
11. (1986)In Ecology, Change brings stability. Science 234: 1071- 1073.