Health & Management / Reintroduction & Conservation Translocation / List of hyperlinked Techniques & Protocols:
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Introduction and General Information

The main priority of conservation should be maintaining natural ecosystems and biological processes. Within this, reintroduction or conservation translocation can be a useful tool in situations where there has been loss of a population or reduction to a non-viable level. (P17.62.w1). 
  • In some cases, translocation of an organism outside the original geographical range of a species may be appropriate for conservation purposes, although this should always be approached with extreme caution, cue to the risks of adverse effects. (B708)
  • NOTE: At all stages of a reintroduction or other conservation translocation programme, from initial feasibility studies to post-release, progress should be assessed and the programme reviewed and adjusted depending on the results of the assessment. (B708)

Before any reintroduction programme is started, a number of factors must be considered which need to be present in order for the programme to have a reasonable chance of success. These include factors related to the species, the habitat/ecosystem, socio-political factors, and funding/support. A feasibility study needs to be carried out before any programme is developed and problems with any of these factors should lead to re-consideration and postponement, alteration or cancellation of the intended programme, as appropriate. 

(B482.14.w14, B708, J727.1.w1, P17.62.w1)

As the science of conservation evolves, definitions develop and change.
  • Re-introduction has been defined as the deliberate release of individuals of a species into an area from which it has been lost, with the aim of establishing a self-sustaining and viable population. (P17.62.w1)
  • Translocation is "the human-mediated movement of living animals from one area, with release in another." (B708)
    • The animals may be moved from the wild or from captive populations, and can be deliberate or (as with animals which stow away on ships etc.) accidental. (B708)
    • Note: Translocation has also been defined in a narrower sense as "the deliberate and mediated movement of wild animals or populations from one part of their range to another." (B456)
    • Translocation has also been used to describe the capture and movement of free-living animals from one location to another location, specifically excluding release of captive-bred animals. (P17.62.w6)
  • Conservation translocation has been defined as "the intentional movement and release of a living organism where the primary objective is a conservation benefit: this will usually comprise improving the conservation status of the focal species locally or globally, and/or restoring natural ecosystem functions or processes". (B708)
    • Within conservation translocation, population restoration involved translocation within the indigenous range of the species, whether reinforcement (intentional movement and release into an existing population of conspecifics of the released organism) or reintroduction (intentional movement and release of an organism within its indigenous range but into an area from which the species has disappeared). (B708)
    • Conservation introduction is "the intentional movement and release of an organism outside its indigenous range.". This may be legitimately carried out for one of two conservation purposes: to avoid the extinction of populations of the focal species (assisted colonisation), or to provide the organism in order for it to perform a specific ecological function which has been lost through extinction (ecological replacement); this generally involves introducing a sub-species or a closely related species of the same genus as the organism which has become extinct. (B708)
    • Note: extreme care is needed when considering conservation introductions, as indicated by the negative and sometimes catastrophically negative impacts recorded from introductions of species to new ecosystems.

(B456, B708, P17.62.w6)

Aims and Objectives
According to the IUCN 1998 Guidelines for Reintroductions, "The principle aim of any re-introduction should be to establish a viable, free-ranging population in the wild, of a species, subspecies or race, which has become globally or locally extinct, or extirpated, in the wild. It should be re-introduced within the species' former natural habitat and range and should require minimal long-term management." (B456)

The objectives may include any one or combination of: (B456)

  • Enhancing the long-term survival of the species;
  • Re-establishing a keystone species in an ecosystem;
  • Maintain and/or restore natural biodiversity;
  • Provide long-term benefits to the local and/or national economy;
  • Promote conservation awareness.


A goal is "a statement of the intended result" which should set out the intended conservation benefit. It is desirable for a goal to be set stating the intended result in measurable terms: the desired number and size of the population to achieve the intended conservation benefit. (B708)

Actions should be "precise statements of what should be done to meet the objectives" and should be measurable (enabling monitoring and assessment of progress), with suggested time scales, indications of expected resources required, and notes on who is responsible for the implementation. (B708)

Published Guidelines linked in Wildpro

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Species Factors

The following species-related factors must be considered in deciding whether or not a reintroduction programme should be started:
  • Is there a need to augment the wild population?
    • This may include the need to increase the number of individuals in the population, the number of separate populations, or the genetic diversity in the wild population.
  • Are there appropriate individuals available for the reintroduction?
    • These may be individuals from another wild population, or captive-bred.
    • If captive-bred, these must be surplus to the demographic and genetic needs of the captive population.
      • This may require adaptation of institutional and regional collection plans for the species in order to provide individuals to be used in the conservation translocation program. (B708)
      • However, the presence of surplus animals in the captive population should not be used as a reason for a reintroduction programme; the programme should not be used as a means of captive population management, to remove surplus individuals from the captive population.
    • Re-introduced individuals should be as close as possible, taxonomically, to the original population (same subspecies/race, if available). (B456)
    • Individuals for the programme "should be from populations with appropriate demographic, genetic, welfare and health management, and behaviour." (B708)
    • Note: release poses considerable challenges for the individuals being released. For humane reasons, release of an individual which has injuries, genetic defects or other characteristics likely to reduce the chance of post-release survival of that individual should be avoided.
  • Will the reintroduction of these individuals jeopardise the wild population?
    • Release of captive-bred or translocated animals should not jeopardise the wild population. Release into an extant wild population may have negative effects on the population and every effort should be made to minimise the risk of such harm through disease, social disruption or genetic swamping.
    • Particularly when captive-bred animals are being released, veterinary screening pre-release is essential to minimise as far as possible the risk of introduction to the wild population of infectious or parasitic disease, genetic problems or any other medical condition which might be transmitted to native animals, whether or the same or another species.
      • There should be veterinary involvement early in planning process to ensure that disease risks can be identified and avoided. (B482.9.w9, J64.12.w5)
    • Consider vaccination against particular diseases prior to release.
    • Consider appropriate quarantine.
  • Is there sufficient knowledge of the biology of the species?
    • The demography, genetics, behaviour, reproduction, ecology of the species should be known.
    • This information may be available from studies in the wild or in captivity.
    • Information from one or more closely-related species may be incorporated.
      • Consideration of possible inter-species differences is important if there is heavy reliance on data from related species.
    • Information needed includes: preferred habitat(s), social groupings (size, structure, seasonal or other changes); territory/home range size of the individual or social group; amount and distribution of the critical requirements for the species, including food, water, shelter/den sites.
    • Decision-making on aspects such as timing for release (season, time of day etc.), the number of individuals to be released and the period of time over which these animals should be released will depend on knowledge of these biological variables.
  • Is there appropriate knowledge of relevant techniques for reintroduction of this species, or is the programme adequately including development of such techniques?
    • Appropriate techniques for the reintroduction of the species (or of a closely related species) need to be known and/or the protocol to be used should include methods for evaluation techniques and improving them.
    • Since techniques will vary depending on species, habitat etc., all programmes need to include research and development as an integral component of the programme.
      • Both a mechanism for evaluation of level of success of the techniques, and a mechanism for improving methods used, must be included.
    • Knowledge of the species' biology should be used to develop protocols such as degree of pre-release acclimatization and/or training.
    • Knowledge of safe and effective techniques for restraint/sedation/anaesthesia are important; these should be tested and evaluated at an early stage. (P17.62.w7)

(B126, B482.9.w9, B482.14.w14, J50.104.w2, J471.2.w2, J727.1.w1, J64.12.w5, P17.62.w7)

Crane Considerations
  • Before cranes are reintroduced, it is important to consider:
    • Have other management techniques been insufficient, and is the survival of the species in the wild in jeopardy? (P1.1983.w4)
    • Have the methodologies which will be used been tested sufficiently so that chances of the reintroduction being successful are maximised? (P1.1983.w4)
    • Is it likely that survival of released individuals will occur at an acceptable level?
    • Is it likely that release will effectively bolster the wild population?
    • Is it likely that the released cranes will remain in the release area or return there to breed?
  • If releases of captive-bred cranes are to occur, it is important that there are sufficient cranes available from which these individuals can be taken. This has been recognised for some time and breeding of cranes has been carried out to ensure an adequate population both for continuing the captive stock and providing individuals for release. (P91.1.w1)
  • For the endangered  Grus americana - Whooping crane, release techniques were first carried out using non-endangered subspecies of Grus canadensis - Sandhill crane (mainly Grus canadensis tabida - Greater sandhill crane); lessons were also learned from the releases of the endangered Mississippi sandhill cranes, Grus canadensis pulla.
Associated techniques linked from Wildpro  

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Environmental (Habitat / Ecosystem) Factors

The following environmental factors must be considered:
  • Causes (biotic and or abiotic) of the decline of the wild population have been recognised and eliminated or controlled. Causes may include:
    • Habitat loss/destruction;
    • Hunting or taking;
    • Predation by non-native species;
    • Lack of appropriate prey (for predatory species);
    • Introduced disease;
    • Environmental pollutants.
  • Presence of adequate, appropriate habitat within the species' original range.
    • This must be protected against further degradation;
    • A large enough area must be available for the released individuals and their descendents reaching numbers sufficient for a viable population.
    • The habitat needs to meet the needs of the species for all life stages, including allowance for post-release movement: depending on the species, this may include that appropriate habitats are required both for breeding and for outside the breeding season, as well as for migration between these sites.
    • The last place at which a particular species or subspecies was known to occur is not necessarily the most appropriate habitat for release.
    • The availability of requirements such as food and water need to be confirmed for the worst seasons and years, not just on average (P17.62.w6).
    • Note: In certain circumstances, introduction into a range not previously occupied by the species, but ecologically suitable (conservation introduction), might be considered.
      • Undesirable consequences are more likely to occur with conservation introduction than with reinforcement or reintroduction. (B708)
  • The habitat should preferable have none of the species present, or the population should be very sparse (restocking).
    • Release of additional individuals into a habitat which is already at or near carrying capacity for the species is likely to result in severe intraspecific conflict between the resident individuals and the released animals, with social disruption and/or competition or resources, which is likely to be detrimental to the resident wild individuals and to the released animals.

(B482.14.w14, B708, J471.2.w2, J727.1.w1, P17.62.w1, P17.62.w2, P17.62.w5)

Crane Considerations
  • The presence of a suitable area of habitat for reintroduction, particularly breeding habitat, for migratory species, is essential. (P1.1983.w4, P87.9.w6)
  • Critical limiting factors for the species need tohave been identified and appropriate action takem to ameliorate causes of the decline of the fre-living population. (P1.1983.w4)
Associated techniques linked from Wildpro
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Socio-political Requirements

  • Gaining agreement from all parties likely to be affected by the reintroduction is important. For birds which may be highly mobile and in many cases migratory, this may be particularly difficult. (P17.62.w5)

Reintroduction programmes must always consider the socio-political aspects of their actions. There should be:

  • No or minimal probable negative impact on the local human population.
    • It is important that the potential costs and benefits of the programme to the local human population should be assessed, and that there should not be any major negative impacts on the local population: if any segment of the local human population will be seriously harmed by the reintroduction programme then it is unlikely to succeed.
    • Released animals should be of minimal risk to human life and property (releasing man-eating timers is unlikely to be productive).
    • The reintroduction should not greatly economically impact any large segment of the local human population in a negative manner; if this is likely to occur, then there needs to be easonable recompence or alternative employment needs to be available.
      • Note that a minor negative economic impact on a small segment of the population can still cause severe negative perceptions of the reintroduction in the local community. This can generally be avoided by incorporating appropriate communication and education into the programme.
    • Reintroduction programmes may also be beneficial to the local community, providing employment directly, or increasing income through eco-tourism.
  • Support from the local community.
    • A supportive local community is important. This support may be present already, or may need to be encouraged.
    • Local community support may be increased by the project providing economic benefits.
    • Conservation education aimed at the local community should explain the aims and objectives of the programme in a manner relevant to the local people. Community education may include lectures or meetings, school visits, positive interest from the media (including newspapers and magazines as well as television or radio), locally-distributed posters, notebooks, T-shirts etc publicising the project, plays or parades and so on.
    • Whenever possible, particularly for international programmes where "outsiders" or "foreigners" are coming into an area, a component of professional education for some local individuals should be incorporated into the programme. This is obviously dependent on sufficient funding, but shows a real commitment to local development and the possibility of turning management over to the local community in the long term.
  • Support from/involvement of relevant governmental organisations and non-governmental organisations (NGOs).
    • All relevant governmental organisations and NGOs should support the reintroduction programme and, when appropriate, be a part of the decision-making process.
    • Most programmes will involved multiple organisations both for approvals required and in implementation of the programme.
    • Officials with negative attitudes can have a large detrimental impact on a programme; it is important to get strong support from all the agencies involved. The project team should include representatives from most of the relevant governmental agencies and NGOs, even though this makes for complex collaboration and cooperation plans/agreements between organisations.
    • Note: Getting local governmental organisations and NGOs involved from the outset provides a framework for handing the programme over to local community in the long term.
    • There must be a clearly defined decision-making structure within the project, including for sensitive aspects such as intervention policies, staff hiring and firing and speaking with the press, in order to minimise conflicts between members of the reintroduction project team. 
      • It is important for these decisions and policies to be worked out before they need to be implemented.
      • A contingency plan should be worked out including criteria for conditions which would lead to the  reintroduction programme being suspended or discontinued (e.g. unacceptable level of mortality, severe unexpected problems.
  • Relevant laws and regulations conformed with.
    • All relevant international, national and regional legislation, treaties, regulations, treaties and guidelines should be incorporated in the planning stage, and complied with.
    • Note: Failure to comply with regulations, legislation etc. and obtain required licences, may lead to a release being stopped by the relevant authorities, even if all other aspects have been prepared correctly.

(B482.14.w14, B708, J727.1.w1, P17.62.w1, P17.62.w4, P17.62.w5)

Crane Considerations
  • Before reintroducing cranes is is important to consider whether there will be sustained public and professional interest through the time of the release effort.
Associated techniques linked from Wildpro  

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For a reintroduction programme to be successful, it is essential that adequate, long-term effort, funding and physical resources are available to cover:
  • Planning stages;
  • The reintroduction;
  • Post-release monitoring and other post-release activities;
  • Cost-benefit analysis of the techniques used.

Funding agencies need to be aware of the fact that changes to reintroduction/conservation translocation plans are normal, and there should be enough flexibility in the budget to enable appropriate changes (based on assessment) to be made.

(B482.14.w14, J471.2.w2, J727.1.w1, P17.62.w1)

Multi-disciplinary Approach
Re-introduction/conservation translocation requires a wide variety of expertise; a multi-disciplinary approach is essential. 
  • The reintroduction team may need to include personnel from zoos and/or private animal breeders (or botanic gardens, if involving plants), veterinary institutions, universities, governmental organisations, non-governmental organisations and funding bodies; field biologists, educators, avicuturists, veterinarians, habitat managers etc. may be needed.
  • Good coordination between the organisations involved is essential.
  • Public education, and publicity in general, should be a part of the project.

(B456, J727.1.w1, P17.62.w1, P17.62.w4)

Crane Considerations
  • Before cranes are reintroduced it is important to consider:
    • Whether funding will be adequate for a prolonged release effort. (P1.1983.w4)
    • Whether appropriate research and support personnel are available for post-release monitoring. (P1.1983.w4)
Associated techniques linked from Wildpro  

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Risk Assessment

The risks of a reintroduction or other conservation translocation either not succeeding, or causing unintended damage, must be considered in advance of any release. Both the probability of a risk factor occurring and the potential severity of its impact if it does occur, should be considered before any release happens. (B708) It is important to consider:
  • Risks to the source population.
  • Ecological consequences,
  • Disease risks.
  • Risk of accidentally introducing an invasive species into the recipient ecosystem.
  • Intraspecific or interspecific hybridization
  • Potential for direct or indirect negative effects on the human population, including via indirect ecological effects.
  • Risks of unexpected financial costs e.g. due to the translocated species unexpectedly becoming a pest which must be dealt with.


Disease/health risk assessment
  • A health risk assessment should be carried out. (J64.21.w12)
    • This should be carried out by personnel who are not involved in making decisions regarding the translocation (or otherwise have a vested interest in the results), and should not be influenced by those who are involved in decision making. (J64.21.w12)
    • Sufficient information must be available on e.g. species of animals and of disease agents in both the source and the destination environments, mechanisms of pathogen transmission, transportation and quarantine facilities to be used etc. (J64.21.w12)
      • It is necessary to have a complete and detailed description of the translocation process in order for the health risks to be assessed. (J64.21.w12)
    • The assessment must be as objective as possible. Where a subjective assessment is required, it is important that this is clearly identified as such. (J64.21.w12)
    • Initially, all the potential health hazards need to be listed. (J64.21.w12)
    • A subset of hazards is then selected for detailed assessment. These are those which: (J64.21.w12)
      • "may be carried by the animals to be translocated from the source ecosystem to the destination ecosystem"
      • and "may infect or cause disease in one or more wild or domestic animal species or in humans in the destination ecosystem"
      • and "may have significant ecological or economic consequences if introduced into the destination ecosystem."
    • For each of the selected health hazards, both the probability that the hazard will occur during the translocation and the magnitude of the negative consequences if it does occur must be assessed.
      • Both the risk to the destination ecosystem from infectious agents potentially carried in by translocated animals, and the probability that the translocated animals will be exposed to a disease agent in the destination ecosystem, and any negative impact this may have on the objective of the translocation programme, must be considered.
    • An overall written statement and explanation of the total health risk must be developed based on the results of the risk assessments for each of the chosen hazards.
      • This must include identification of the principle sources of uncertainty within the risk assessment.
    • If additional non-health hazards are identified, these must be reported.
    • Changes to procedures which may reduce identified risks should be described. These might include changes in the source or destination environment, transportation, quarantine etc.
    • Note: generally, the risk assessment will be qualitative rather than quantitative and may be framed in terms of high, moderate, low or negligible risk.


Crane Considerations
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Authors & Referees

Authors Debra Bourne MA VetMB PhD MRCVS (V.w5)
Referee --

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