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Dear Mr. Sommer:

I have to admit that I love your talent for fusing poetry and truth so that the result in the end is half an hour of misinformation with homogeneous and biased content. It is a mature and intellectual efficiency. And also, to hide like a wolf in sheep’s clothing, because before so much criticism he sings the praises of zoos; it’s something, with all the bad intentions, well done.

Of course, you can, like anyone else who wants to make his opinion public, spread “fakes” freely around the world. I do not blame you for that. But some of your demands cannot remain unanswered:

1. You claim that the principle of zoos is generally that of “Animal Hoarding”. The animals are supposed to be collected, almost addictively, like vinyls or vintage cars.

This is not correct, although you are thematizing it twice. According to WIKIPEDIA, “Animal Hoarding” is defined as the possession of a collection of animals by an individual in a manner that lacks all the minimum requirements for hygiene, food and veterinary care. The person is not able to understand the consequences of these deficiencies on the health of the animal, the family members and the environment. The person tries obsessively to maintain the situation, and although conditions appear that are increasingly worse for animals and people living together, they deny and trivialize them. Applying this term to an institution which has an operating license under animal and nature conservation legislation, where all the regulations required by law are met, and which has a large staff of qualified animal keepers and is also under permanent veterinary control and official veterinary supervision, should comply with the fact that it is a defamation offence, according to § 187 of the German criminal code. On the one hand, you overlook the fact that names such as Wildlife park, Aquarium, Reptile Zoo, Bird Park, Domestic animal park, Butterfly Garden, which you break down meticulously, albeit incorrectly by percentage (your figures are far from correct, the Zoo-AG lists not 400 but over 1,000 zoological institutions for the German-speaking world), already imply a self-limitation. On the other hand, it is easy to see that zoos have long been far from the beginnings of a collection and that the average number of species present in each zoo, for at least half a century, is decreasing in favor of space and quality of life. Partly in such a way that coordinated breeding programs are in danger. [DOLLINGER, 2014].

2. You claim that zoos are hardly subject to legal regulations.

This is false and shows absolute ignorance. There are few activities that are more regulated than the maintenance of zoos, starting with a European zoo regulation, an EU species protection regulation, an invasive species regulation and, in addition, many veterinary regulations. At the national level, animal, species and nature conservation laws and the licensing obligations based on them ensure that no irregularities occur. In Switzerland and Austria, detailed minimum requirements are laid down for the maintenance of the various animal species. In Germany, there are reports from the ministries, which are regularly checked by official veterinarians. The profession of animal caretaker and the availability of certificates of competence are regulated, as are the safety requirements.

3. A proof of the superficiality of their investigations

Your statement that WAZA has 250 members and of these a dozen in Germany is incorrect. At the end of 2017, WATA did indeed have 278 institutional members, 36 of them in Germany. Calculating correctly, this is three dozen.

4. You refer that WAZA and VdZ members meet the established standards of the organizations

But you do not take into account that the European association for zoos and aquariums, which has a much more detailed accreditation procedure and regulations or “Best Practice Guidelines”, already has more than 100 additional members, who are not included in the WAZA figures and that the Deutsche Tierparkgesellschaft (DTG) has almost completely taken over the annex on minimum requirements for member zoos. This is why another 100 zoos are integrated. Also, zoological organizations outside the German-speaking area and regional organizations on other continents have rules and some accreditation procedures for their members.

5. You imply that nature has been exploited by zoos and to stop this, CITES rules were introduced in 1973.

Apart from the fact that the CITES rules have not existed since 1973, but since 1 July 1975, at that time in 10 related countries, in the Federal Republic of Germany from 20 June 1976 and in Austria from 27 April 1982 (again poorly investigated), this is a reversal of the facts. Only in very few cases did zoo activity have a negative impact on the wild population and, long before CITES, they introduced self-limitations when they realized that this has happened as in the case of orangutans and musk oxen. Since then, the association of zoo directors, WAZA’s predecessor, has been one of the few organizations that required the community of nations to establish international regulations to control and limit trade. Indeed, under CITES, for species listed in the annex, there is a ban on trade in wild specimens taken from the wild. Trade in specimens from breeding and non-commercial trade are still permitted, if the necessary documentation is available. Finally, the problems that were still to be solved by CITES have not been caused by zoo animals, but by the trade in cat and otter skins, crocodiles, snakes and turtle shells, ivory, rhino horns, vicuña wool and other animal products, ornamental plants and tropical woods. As for the animals, these were species, which were used on a large scale for purposes other than the conservation of zoos. For example, primates for biomedical research and turtles, lizards and parrots for private use as pets.

6. You imply that the introduction of trade restrictions put pressure on zoos because they had to reduce the mortality rate of the animals they housed.

There is no causal relationship here. If you do not want to accept that zoos act ethically, you should at least admit that, from an economic point of view, it makes a lot of sense to treat your animals in such a way as to ensure their longevity. Especially institutions that are not very rich. No zoo can be interested in having its animals die. Apart from that, most animals living in zoos are not listed in CITES or are listed in Annex II, and so they are part of Article IV of the agreement, which makes no demands on the receiving companies. That is why their arguments are no longer valid from the outset. A reduction in the mortality rate was achieved after the Second World War by several factors. On the one hand through Heine HEDIGER’s book “Wildtiere in Gefangenschaft”, in which he defines zoological biology as a scientific branch. Therefore, the understanding of animals and their needs increased and breeding was improved. New knowledge led to healthy feeding, which was also possible with species where this was not previously the case. The evolution of veterinary medicine developed a multitude of antibiotics, antiparasitic and preventive vaccines and new disease treatments. Thanks to new drugs for anaesthesia and immobilization and the possibility of applying them also at a distance, incidents decreased while animals were being moved or transported. In addition, an exchange of experience between zoo veterinarians was established through the zoo disease symposium and the zoological veterinary consortia invested heavily in the training of their members.

7. You say that the four-pillar concept was developed through CITES as a friendly offensive. It would not be the basic foundation, but a post-invent of the zoological institution and its character of a relaxing place was put, out of shame, at the end of its functions.

In this case you already have several errors: already in 1948, when you were not even born, HEDIGER had published an article under the slogan “The zoo a place of asylum and scientific studies”. In this case, asylum meant both protection of species and individual animals. In 1965, in his book “Mensch und Tier im Zoo: Tiergarten-Biologie” (“People and animals in the zoo: zoological biology”) he spoke about the seven aspects of a zoo and on 26 May 1973 he summarized his demands on a zoo, which he had repeatedly referred to, in a lecture published later at the General Assembly of the Naturforschenden Gesellschaft (Natural Science Society) in Zurich, as the principle of the four pillars. All this happened before CITES was established as a reference. With regard to science, it should be noted that at the beginning of the 19th century the first scientific description of numerous animal species was made by zookeepers and based on zoo material, e.g. by Georges Cuvier, Frédéric Cuvier, Étienne Geoffroy Saint-Hilaire de la Menagerie de Paris or by Martin Hinrich Lichtenstein and Wilhelm Carl Hartwig Peters of the Berlin Zoo. This continues to this day, for example, when a new lizard from Vietnam was discovered in 2005 by a team including the director of the Cologne aquarium, Thomas Ziegler, and named Gekko scientiae-adventurae, with reference to the television program “Abenteuer Wissen”. As early as 1859, the Frankfurt Zoo published the scientific journal “Zooologischer Garten” (“Zoo Garden”), which quickly became the “central organ of zoological gardens in Germany”. From 1959, the reports of international symposia of zoo veterinarians were published annually, and from 1960, the “International Zoo Yearbook” was added as a scientific journal in English. In the 2005 World Zoo and Nature Protection Strategy, 27 scientific journals are published by zoos or receive their knowledge regularly from zoo studies.

Since 2013, the EAZA publishes the “Journal of Zoo and Aquarium Research” online. As early as 1958, Prof. Heinrich Dathe of the Tierpark Berlin-Friedrichsfelde Zoo established a research center for vertebrate animals, today known as the Leibniz Institute for Zoological and Wildlife Research. Since 2014, the Opel-Zoo has been financing a professorship at the faculty of biological sciences of the Goethe University in Frankfurt am Main as the first zoo, and in 2016 the Frankfurt zoo followed suit. As far as nature and species protection is concerned, it should be remembered that the first breeding to conserve endangered species, which resulted in successful resettlement projects, was carried out decades before the introduction of CITES. Specifically, 1905 for the bison, 1906 for the mountain goat, 1923 for the European bison and 1957 for the Przewalski horse and, shortly thereafter, for other species. In the meantime, 14 species that had disappeared in the wild completely and more than 200 species that had disappeared regionally were resettled. The zoos fulfilled the educational task at first mainly through teachers and chairs at the universities and through information panels in front of the nurseries and guided tours by zoo employees for the public. In 1958, European zoos started to employ the first zoological professor in London and in 1960 they employed the first zoological educator in the Frankfurt Zoo to fulfil their educational task. Today, 86% of the VdZ-Zoos have a zoological school. The 71 zoo members have 861 employees who are engaged in educational work. The educational offerings of the zoological schools, such as lectures and guided tours, are perceived by 1.1 million people per year, and the “Keeper’s Talks” and commented meals are not included in this estimate. Some years ago, the German association of wildlife reserves introduced a qualification offensive that focuses on education for sustainable development. The aim of the educational offer is to ensure that the parks participating in the seminars acquire knowledge and skills on the subject of sustainability, in order to develop as individually as possible on their own premises. This multi-grade offer is very well accepted by the parks. The recreational function does not appear with Hediger, as you say, embarrassed in the last position, but in the first. This chronological order was also maintained in the anniversary book of the VDZ “Gärten für Tiere – Erlebnisse für Menschen” (“Gardens for animals, experiences for humans”) published in 2012. In 2005, WAZA sees its global zoological strategy for nature conservation as having a recreational function. And it sees the stay in a natural environment and the direct encounter between human and animal as an opportunity to raise the awareness of visitors for the protection of wildlife and nature. An example of the perception of the four pillars is the Opel Zoo, which has been demonstrating its commitment to the public through figures since 2016. Here are the figures for 2018:

• First pillar – recreation: 545,000 visitors
• Second pillar – training: 20,400 people served by zoo educators
• Third pillar – research: 18 papers completed and supervised by the Opel Zoo Chair
• Fourth pillar – conservation: breeding animals for 7 reintroduction projects and 3 new species in the breeding program

8. You claim that hedonistic needs are the main reason for a visit to the zoo and the only one that fills the cash registers. The mega-zoos misuse animals as decoration for gala dinners and the animals are instrumentalized and exploited.

The fact is that zoos are more popular than ever and the numbers of visitors are increasing every year. But are the reasons for visiting a zoo really based on hedonistic needs? My former co-worker and good colleague, ethologist Dr. Thomas Althaus, does not believe that entertainment is the reason, but neither does the desire to acquire much sustainable knowledge. Beyond that, he sees the desire to meet animals face to face and to understand them through their bodies, their nature, their smell and their movements. This would have nothing to do with intellect but with intuition, emotional level, admiration, reverence. The zoo transmits sustainable experiences and emotions. In some circumstances, a stay of less than a minute in front of a nursery may be sufficient.

It is correct that zoos use human needs to generate income. This is necessary because, although a zoo has much higher fixed costs than any other cultural institution, they are subsidized to a much lesser extent than e.g. museums or theatres. If this were not the case, they could refrain from charging admission fees. A couple of examples: in 2007, the city of Frankfurt subsidized its zoo with 6,7 million euros, which is equivalent to a subsidy of EUR 7.33 per visitor. In the same year, it also covered the deficit of the opera and theatre, which means that for every ticket sold, it paid an additional in 2011, the Berlin Senate subsidized the zoo and aquarium with 1,3 million euros and the animal park with 5,7 million euros. This is equivalent to EUR 1.91 for each visitor to the capital’s zoos. In contrast, each visit to a municipal indoor swimming pool is subsidized with EUR 4.80 and a visit to the Friedrichspalast with EUR 14. Each ticket to the opera is co-financed with EUR 186, tickets to the municipal museum foundation with EUR 61. All this is a multiple of the subsidies that zoos receive. The city of Basel supports the zoo, a non-profit corporation, with the equivalent of 800,000 euros annually, which is about EUR 0.70 per visit. At the same time, it subsidizes the theatre with reference to the 165,000 visitors to the theatre, this is equivalent to a reduction, financed by the city, to the value of EUR 145 for each ticket sold. The Museum of Historical Nature in Basel, with 97,064 visitors (in 2010) received 5,677,500 euros, i.e. EUR 58 per visitor.

As far as the instrumentalization and exploitation of animals is concerned, this is something that may upset you and other animal rights activists, but the animals don’t care. If a fish were intellectually capable of such thought processes, he would certainly prefer to be observed at the large aquarium by the guests at a gala dinner eating mounds of salmon instead of lying on the ice in the fish market hall waiting to be eaten himself.

9. You claim that most visitors to zoos learn nothing about biology and nature conservation, at least this is not proven by any reliable studies.

To verify your claim, you will have to present a reliable study, which shows that most visitors learn nothing. Secondly, you will have to argue why the works of JENSEN et al. (2017), MOSS et al. (2014), MOSS et al. (2017) and SMITH et al. (2008), which demonstrate an educational effect and which were published in peer-reviewed journals, are not reliable. The work of JENSEN (2014), which is used by animal rights activists, has the weakness of being based only on one zoo and on visitors of a certain age group. Furthermore, he concludes: “forty-one percent of educator-guided visits and 34% of unguided visits resulted in conservation biology-related learning” and “Overall, my results show the potential educational value of visiting zoos for children”, which shows that this work that GOLDNER uses against zoos, can also be cited in their favor.

If you question the effectiveness of zoos in terms of environmental education, you should also make a comparison with nature conservation organizations: the WWF spends 650 million euros annually, mostly to raise awareness among citizens for the protection of nature and the environment. In the case of Greenpeace, 240 million euros are spent, mostly on public actions that attract attention. Has the world improved because of that? Do people give up on buying an SUV? Do they deprive themselves of a trip to New York or London for a weekend to buy a few shirts or shoes? Do they replace their big vacation in Mallorca with one in Bavaria? Are Germans switching to more environmentally friendly railways instead of staying in traffic jams for more than 450,000 hours a year, with a growing trend? Are many people turning their barren gardens into natural gardens? Why has fish consumption in Germany increased by 30-40% since the 1980s? Why do we produce more rubbish than before? Obviously neither the educational work of environmental activists nor their appeals are of any use. Then we must, following their logic, put an end to environmental organizations.

10. You accuse zoos of identifying cages and nurseries, with strategic words, as a home.

It is a fact that animals do not have the abstract concept of freedom. They demand from their environment, in the sense of maintaining themselves and the species, certain conditions. If these conditions are met, they consider this environment as their home, whether it is a certain area in the forest, a redwood in the savannah, a rocky wall in the mountains or a zoo enclosure. This is not a “new interpretation of a word”, but an understanding that was already discovered in the first half of the last century, according to which the animals in the zoo are not prisoners, but landowners. [HEDIGER, 1942].

11. You claim that scientific management allows zoos to be classified as non-commercial, allowing them to acquire “CITES Red List” animals.

This is completely false and shows that you have no idea of the mechanisms of CITES. There is no “CITES Red List”. Wild catches from the CITES annex, according to article III, may not be imported for primarily commercial purposes, which allows each public zoo, any SL or SA not-for-profit, foundation or association to import. Scientific purposes are not necessary for the classification as “non-commercial” and have absolutely nothing to do with management. Furthermore, membership of the Association of Zoological Gardens (VdZ), which only includes scientifically managed zoos, is not based primarily on the academic qualifications of the zoo director, but on a six-page catalogue of requirements with 50 criteria.

12. You claim that zoo research serves exclusively to support itself and that comprehensive strategies for basic research are lacking.

The fact that zoos are looking for new knowledge to improve animal husbandry is not only a demand of animal welfare organizations, but also of the state. But it is false that this is the only aspect of zoological science, and this can easily be seen from the many papers that have nothing to do with breeding. His statement that there was no comprehensive strategy is another example of his botched research: Already in 2008, EAZA published its Research Strategy and in the Welt-Zoo-Naturschutzstrategie of 2005 an entire chapter is dedicated to scientific studies and also includes a wide spectrum of possible research fields.

13. You claim that one could calculate in one hand the scientific groups located and funded by zoos.

If you had made the effort to search for GOOGLE “zoo+research+department”, you would have obtained 41,000 results in only 0.6 seconds. Reading the first four pages, you would have found 20 zoos that maintain a “research” or “science.” You don’t even have that many fingers. Research is basically not a compulsory task for zoos, but is included as an option in both the EU Zoo Directive and national legislation. In fact, of the 1,000 zoos in the German-speaking area, only 70 claim to carry out or promote scientific studies. The other 93% who do not argue in such a way their criticism that research is a by-product or is used as a fig leaf is useless. That the remaining 70 VdZ-zoologicals do not invest more money in science can be understood if one considers that they do not receive any understanding from the public purse and it is easy to criticize if, as is the case with you, you are employed by an institution that is subsidized to three digits and receives millions from the state.

14. You claim that many species, for which conservation through breeding programs exist, are not endangered and are not reintroduced into the wild through such programs either. Therefore, zoos themselves are the beneficiaries of these breeding programs.

It is a fact that zoos are also involved in the keeping and breeding of species that are not endangered. But you forget that zoos also have other tasks for which they need animals. Contrary to what animal activists think, who do not agree that the same effects could be achieved through digital animations, titling zoos in this relationship as beneficiaries, which implies that they generate profits. But this is usually not the case, with a few exceptions, zoos are non-profit institutions.

15. You point out that the financial support of zoos for in situ conservation projects is minimal.

First of all, it is unscientific to conclude that the results of a zoo, which is also located in a province, are not scientific to the whole zoo community. According to WAZA, its members support in situ projects with more than 300 million CHF each year. With these figures, the zoo collective is the third largest organization for nature protection worldwide, after WWF and Conservation International. In addition, in recent years, zoos have increased their efforts to support in situ projects, e.g. by applying a nature conservation fee to each ticket sold. The Augsburg Zoo, for example, has increased the price of each ticket since 2009 by 10 cents for nature conservation, and the Karlsruhe Zoo has increased it by one euro since 1 January 2019. In the Basel Zoo, which has been using this system since 2016, it was only possible to raise CHF 346,000 in 2017, which is almost as much as the Wilhelma, to which you refer, has spent in 23 years on on-site projects. Apart from this, the financial contributions are only part of the services provided by the zoos. In addition, the zoos contribute know-how, staff, knowledge exchange, public relations and infrastructure. All this cannot be quantified in concrete terms.

16. Animal welfare.

It is symptomatic that animal rights activists always refer to the poem “Der Panther” by Rainer Maria Rilke. This poem was created in 1902, when Emperor Wilhelm was still ruling the German kingdom. It describes the conduct of a panther in a zoo that was built 200 years ago (1817 – 1821) and was destroyed in 1936, i.e. more than 80 years ago. To claim that there was no improvement in the keeping of animals in the last 80 years is either stupid or malicious.

Your claims that life expectancy in zoos is shorter and that animals automatically develop stereotypes due to the fact that, compared to their natural territories, they live in a limited environment outside problematic etc. can possibly be applied to some cases, but cannot be generalized. Especially time has to be considered. One cannot compare a zoo from the year 1900 with one from 2000. It is unacceptable to compare the maximum age in nature with the average age in zoos. An intact elephant population, living in the savannah of southwest Africa, is growing by 6% annually. When the tolerable density is reached, 6% of the animals inevitably have to die each year. That means an average age of 15 years. This data shows that the age of 56 years that you quote for African elephant females is irrelevant and the balance is in favor of zoos. The comparison between Asian elephants in logging camps and breeding in Europe is not possible, because most of the births of elephants in Europe occurred in the last 20 years and therefore the average age of the elephants has to be automatically below 20 years. In 2018, 5 female elephants died in German zoos, which were taken from their natural environment. They were on average 51 years old – 9 years older than the elephants of the loggers. As is the case for many species, the life expectancy of great apes or common dolphins in the much criticized dolphinariums is already higher than in nature.

Having a territory is not a challenge for an animal, unlike humans. It requires nothing more than its territory, to have sufficient food and infrastructure to support itself and its species. Its size varies for the same species depending on the conditions. A lynx in the western Swiss Alps needs about 80 km² to beat its 50-70 deer or chamois per year. A lynx that arrives in an area in the province of Wallis, where a forest ranger introduced deer feeding reduces its radius of action to a few hundred meters, while it can come down weekly from its tree to hunt its deer in the vicinity of the feeding ground. The same is known about wolf packs in Canada, which feed on bison living in fixed territories. In zoos where food is provided, the territory can be much smaller, without causing problems for the animal.

17. The future of zoos.

Your ideas about how zoos should be changed are not achievable as long as the public coffers are not willing to subsidize zoos in the same way as museums and municipal theatres and as long as activists behave as if they were the lifeblood of society, even though they are in fact a marginal group. Their idea of closing zoos and gathering collections on spacious islands is unrealistic. Where is an uninhabited island without its own fauna, where only the 1,600 tigers registered in the international breeding book can be reintroduced under conditions that are better than in zoos, and where do they get the millions to create individual nurseries for these animals that live alone? And if you were to release these animals on this island without the necessary infrastructure, you would cause nothing but murder and manslaughter on a large scale. Where would the money come from to feed the tigers 2,5 million kilograms of meat a year? And this is only one species out of a few thousand that you intend to resettle. The change in the Buenos Aires zoo, named by you as an example, seems to be turning into a catastrophe. Only a few animals were found and the mortality rate is increasing. By the way, how do you even know that an animal born in a zoo by zoo-born parents felt more comfortable in a sanctuary of your choice than in its natural habitat or a comparable enclosure? Even a biodome will not work in the long run. People would only go once, and then never come back, because they would lack the unique experience that is found in direct contact with the animal. Erich von Daniken’s Mystery Park, which was based on this concept, broke down after only three years. In contrast, the Berlin Zoo has existed for 165 years and together with its aquarium has 3,5 million visitors a year.