The conservation measures acting directly over the natural habitat (in situ conservation) can be extremely varied, including programs to raise awareness of local populations, habitat improvement, etc. The Lisbon Zoo participates in situ conservation of various animal species. It collaborates in various forms and establishes working partnerships with entities in the frontline of action in Nature.

In 2005, the Lisbon Zoo was distinguished with the award for Best Conservation Program of the EAZA - European Association of Zoos and Aquaria - as coordinator of the in situ conservation program  for the Silvery-brown Bare-face Tamarin (Saguinus leucopus), in Colombia. In July 2006, this program was also recognized by the IUCN, and came to be supported by it thereafter.

The conservation measures adopted for each species under human care, i.e., outside their natural habitat, reflect the meaning of ex situ conservation. The survival of species often depends on keeping animals under human care, watching over their reproduction and the formation of healthy and genetically viable populations. Thus, the linkage between zoos and similar institutions, and the proper management of populations at the European and international levels, is essential for the survival of the species. There are countless institutions and associations working together with this same mission. 

The animal species a zoo has in its care are selected with the utmost caution. The goal is to plan the collection of animals and, for this reason, the institutions rely on Taxon Advisory Groups (TAGs): working groups formed by specialists who are dedicated to specific groups of animals. For example, the Penguin TAG, the Elephant TAG, among many others.

The TAGs develop Regional Collection Plans that describe what species are recommended, why, and how to manage them. They are an important work basis for each zoo and for the conservation of species at the global level. These collection plans also indicate which species should be put under additional protection through other conservation programs.

Conservation under human care is still characterized by a strong component of Environmental Enrichment, through which the natural behavior of the animals is stimulated. This is currently recognized by the IUCN – the International Union for Conservation of Nature - as an essential instrument for the conservation of biodiversity.

The European Endangered Species Program (EEP) allows for zoos to jointly keep genetically healthy populations, so that they may breed with the ultimate aim of reintroducing into their natural habitat. This program is very intensive and includes demographic and genetic analyses, and the preparation of plans for the future management of species, always in view to promote their reproduction and the formation of healthy and stable populations in order to conserve them. 

The European (ESB) or International (ISB) Studbook is a registry of data pertaining to a given species. In other words, it is a document similar to a genealogy book which records deaths, births, affiliation, and transfers of all zoos that keep the species in question. It allows us to know how many individuals there are of a given species, who their progenitors are, their offspring and under which zoo’s care they are under and, well... a pool of information that is essential for the articulation of information and individuals among zoos and parks all over the world. 

The Lisbon Zoo began its participation in the EEPs in the early 1990s with four programs, currently taking part in 5 TAGs and 64 EEPs. In regard to studbooks, the Lisbon Zoo participates in 44 European and 48 international ones.

The Zoo is a member of organizations dedicated to the conservation of species and their habitats, as is the case of EAZA (European Association of Zoos and Aquariums). This year, since 2000 the Zoo has participated in all the conservation campaigns carried out by EAZA for conservation projects in situ, striving to publicize them and raise funds for a new campaign.