Reacción a "The ageing of animals jeopardises the conservation objectives of zoos"

It is a very high-quality article. It uses very accurate population pyramid data (since the age of animals in zoos is known with absolute certainty) and analyses a large number of species, making the results very reliable.

It is empirical evidence of what has been widely known and debated for several decades in the zoological sector. In zoological environments, animals live much longer, and this creates an altered population pyramid (since the population is controlled so as not to compromise the welfare of the animals due to lack of space). In nature, predators, parasites, lack of resources, and disease keep the population in balance and prevent a high proportion of geriatric animals. The problem is that this altered population pyramid in zoos reduces their conservation potential and jeopardises their positive impact on conservation. The constant increase in species with conservation problems puts further strain on the situation and means that the space available in zoos is increasingly in demand for new species.

From the point of view of biodiversity conservation, the role of zoos is very clear. Both the International Union for Conservation of Nature (IUCN) and the Convention on Biological Diversity have recognised that zoos and captive breeding play an essential role in combating the biodiversity loss crisis. The IUCN has even called on zoos and aquariums to redouble their efforts in the fight against what is already being called the sixth great mass extinction. On the other hand, the European Zoo Directive and the Spanish Zoo Law make the role of zoos and aquariums in biodiversity conservation crystal clear.

This article highlights the biodiversity conservation problems that can arise if indiscriminate bans on population control in zoos become widespread due to the extreme ageing of their populations. In some countries, such as Spain, regulations prohibiting euthanasia for population control have been enacted, driven by animal welfare organisations with an urban philosophy. This situation is viewed with great concern in countries such as Germany, Denmark and the Scandinavian countries, as it will jeopardise the ability of zoos to maintain genetically diverse populations capable of producing individuals for reintroduction.

The real problem is reconciling the needs of animal population management to maximise their capacity for biodiversity conservation with the demands of animal welfare organisations, whose philosophy is opposed to captivity. This article provides clear evidence supporting the need for zoo population management based on biodiversity conservation objectives.