(Timeline adapted and expanded from Vernon N. Kisling, “Historic and Cultural Foundations of Zoo Conservation: A Narrative Timeline,” in The Ark and Beyond.)



The Philadelphia Zoo is established

Philadelphia zoo 1859

This zoo, which opened its gates in 1874 due to the Civil War, is considered the first “true” or modern zoo in the U.S.



Man and Nature is published

Written by Vermonter George Perkins Marsh, Man and Nature, or Physical Geography as Modified by Human Action, is widely considered one of the foundational texts of the American conservation movement.



The Cincinnati Zoo and Botanical Garden opens

Cincinnati Zoo 1875

The second-oldest zoo in the United States, the Cincinnati Zoo was active in early animal breeding efforts, including the first captive bred sea lions.



The Woods Hole Science Aquarium is established

Woods Hole Science

Considered by many to be the nation’s oldest aquarium, this small public aquarium is run today by the National Oceanic and Atmospheric Association (NOA) in partnership with the Marine Biological Laboratory.



The National Zoological Park opens

Designed by the prominent landscape architect Frederick Law Olmsted, the National Zoo (located in Rock Creek Park in Northwest Washington, D.C.) is part of the Smithsonian Institution and is one of the nation’s oldest zoos. A second zoological campus, the Smithsonian Conservation Biology Institute in Front Royal, Virginia, focuses on endangered species and habitat conservation. [Photo: William T. Hornaday, one of the Zoo’s original planners]



The New York Zoological Society is chartered

New York Zoological Society

The NYZS was committed from the start to encouraging an interest in zoology among the public, as well as a concern for wildlife protection. In 1899, the New York Zoological Park (aka Bronx Zoo) was established, which becomes one of the nation’s flagship zoos and an early leader in captive breeding, wildlife reintroduction, and species protection. The NYZS evolved into the Wildlife Conservation Society (WCS), which not only runs the Bronx Zoo, but also the Central Park Zoo, Queens Zoo, Prospect Park Zoo, and New York Aquarium. Today the WCS is engaged in wildlife and wildland conservation in scores of projects around the world.



The Lacey Act is passed

The Lacey Act provided a national effort in the United States to enforce many existing state laws protecting wildlife—primarily game species. Although the law was a modest effort that controlled interstate commerce of these protected species, future expansions of the act provided substantial wildlife protections, including regulating the acquisition, trade, and transport of wildlife among zoos.



Penrose Research Laboratory is established (Philadelphia Zoo)

Penrose Research Lab

The lab’s purpose was to study wildlife health, nutrition, and husbandry. It produced some of the first zoo feeds that incorporated the necessary nutrients for each species and led the way in veterinary care for tuberculosis, a very important advance because of the loss of animals to TB in early zoos.



The American Bison Society is formed

American Bison Society

The organization’s goal was to protect the species (Bison bison), which had become extinct in the wild. Reintroduction of bison into wild reserves began in the early 1900s. William Temple Hornaday, director of the New York Zoological Park (aka Bronx Zoo) in the early 20th century, led the effort to create this society and its bison reserves. Bison from his zoo, other zoos, and private herds provided the stock for these breeding efforts, which eventually succeeded in reestablishing herds.



The scientific journal Zoologica is launched by the New York Zoological Society

Although several zoo magazines had been published since the mid-nineteenth century, Zoologica presented research conducted at the Bronx Zoo as well as the society’s field studies. It was discontinued in 1973, but in 1982 it was replaced with the commercially published Zoo Biology, which covers research from all zoos.



Our Vanishing Wild Life is published

Our Vanishing Wild Life book

Written by William T. Hornaday, the book was an assessment of the wildlife conservation situation at the time and today is considered a precursor to the more modern Red Data Books published by the IUCN.



The last passenger pigeon (“Martha”) dies at the Cincinnati Zoo

The species, which once numbered in the billions, was decimated by market hunting in the 19th century. By 1900 it was extinct in the wild. The pigeon’s disappearance would become a rallying point for wildlife conservation in America in the second half of the 20th century. Today, the passenger pigeon figures prominently in high-tech efforts to “revive” lost species, a project referred to as “de-extinction.”



The New York Zoological Society establishes a field research station in British Guiana

Although not specifically meant for conservation purposes, the research station marked an early effort by a major zoo to embrace science and in-situ field studies. [Photo of NYZS naturalist William Beebe in British Guiana in 1917].



Zoological Society of San DiegoThe Zoological Society of San Diego is formed

The San Diego Zoo would open to the public in 1923. Today, it is one of the nation’s largest and most prominent zoos, with a global profile in zoological research and wildlife conservation. A second facility, the Wild Animal Park, was opened in 1972. Designed as an animal breeding and conservation center linked to the zoo, the Wild Animal Park featured larger and more naturalistic enclosures, and offered a more immersive experience for visitors. It was renamed the San Diego Zoo Safari Park in 2010.



The last Carolina parakeet dies at the Cincinnati Zoo

last Carolina parakeet diesA bird endemic to the eastern United States, the Carolina Parakeet was common until the early 19th century, when hunting pressure (for food and feathers, as well as to protect crops) and forest clearing for agriculture led to the species’ decline. The last birds to be confirmed in the wild were taken in 1904.



The American Association of Zoological Parks and Aquariums (AAZPA) is established

Association of zoos and aquarium graphic

The organization began as an affiliate of the American Institute of Park Executives (later the National Recreation and Park Association / NRPA). AAZPA had a Conservation of Wild Life Committee from the start. In 1972, the AAZPA became an independent organization and shortened its name to the American Zoo and Aquarium Association in 1994. Today it operates as the Association of Zoos and Aquariums (AZA), and serves as the main accrediting body for American zoos, promoting standards for conservation, science, education, and recreation across a zoo and aquarium network encompassing more than 230 institutions.



John G. Shedd Aquarium opens in Chicago

John G. Shedd Aquarium

Containing both freshwater and saltwater aquaria (a novel design feature at the time), the Shedd Aquarium would become a leader among public aquariums in the areas of marine conservation and sustainability. In 2012, it established the Daniel P. Haerther Center for Conservation and Research, which supports research and conservation efforts around the world.



The International Union of Directors of Zoological Gardens is established

The International Union of Directors of Zoological GardensFounded in Basel, Switzerland, the IUDZG would expand and eventually rename itself the World Association of Zoos and Aquariums (or WAZA). WAZA promotes cooperation among a diverse global assembly of zoos, aquaria, and other organizations devoted to the breeding, care, and conservation of animals.



The International Union for Protection of Nature is formed

International Union for Protection of Nature iconThis organization, which in 1956 changed its name to the International Union for Conservation of Nature and Natural Resources, or IUCN, created the Species Survival Commission (SSC) in 1949 and the Conservation Breeding Specialist Groups (CBSG) in 1980. Today the IUCN is the leading global clearinghouse facilitating the sharing of scientific information among zoological and environmental organizations and governments regarding the conservation of species and the safeguarding of parks and protected areas, including dissemination of the “Red List” of threatened species.



A Sand County Almanac is published

A Sand County Almanac book coverWritten by the forester, conservationist, and amateur philosopher Aldo Leopold, this collection of nature essays and reflections would become one of the most influential texts in American environmentalism. In particular, Leopold’s call for a “land ethic” to govern our relationship with wild species and with nature as a whole would inspire generations of conservationists (including in zoos and aquariums).



The Arizona-Sonora Desert Museum opens

Located outside of Tucson, this “biopark,” a combination of zoo, botanical garden, natural history museum, art gallery, nature center, and aquarium, focuses on its home region, the Sonoran Desert.  Its collections include only native animals and plants, a place-based approach that emphasizes education and local and regional conservation efforts.




The World Wildlife Fund (WWF) is established

One of the oldest and most influential international conservation organizations, the WWF (subsequently renamed World Wide Fund for Nature) supports scores of species conservation projects and wilderness protection efforts around the globe, producing its authoritative Living Planet Report every two years.



The IUCN Red Data Books

A generic term used for publications that assess the conservation or endangered status of species, “Red Data Books” was first used in the 1960s when the IUCN published books under this title, with red bindings. However, precursors existed: Hornaday’s Our Vanishing Wild Life in 1913, three publications of the American Committee for International Wildlife Protection (two for mammals in 1942 and 1945 and one for birds in 1958), and the International Council for Bird Preservation’s publication on the status of birds in 1958. Many Red Books/Lists have since been published at the international, national, and regional levels. Today, the IUCN’s Red List of Threatened Species is the leading global record of the conservation status of the world’s biodiversity.



Silent Spring is published

Authored by marine biologist and nature writer Rachel Carson, Silent Spring assessed the effect of pesticides and pollution on the loss of wildlife species. It also had a significant influence on the growing environmental movement in the 1960s and early 1970s, a time of widespread public awareness of environmental degradation, loss of wildlife habitat, and the plight of endangered species. It’s a period that resulted in new environmental legislation, important wildlife conservation efforts, and major changes in zoo husbandry and management.



The Maytag Zoo opens in Phoenix, Arizona

In the early 1960s, the zoo (which would soon be renamed the Phoenix Zoo) housed the “World Herd” of Arabian oryx as part a collaborative effort to save the species from extinction.  Although the animal was declared extinct in the wild in 1972, a coordinated breeding and reintroduction program eventually led to the establishment of managed populations in the Middle East, making it one of the great success stories in zoo conservation.



Man and Animal in the Zoo is published

Written by the Swiss zoologist Heini Hediger, this book (published in 1963 in German, with a US edition in 1969) established the scientific perspective of captive husbandry known as zoo biology.



The Laboratory Animal Welfare Act is passed

Expanded in 1970 to include animals exhibited in zoos, the AWA requires licensing and determines the management criteria for species kept in zoos.




Earth Day

On April 22, 1970, the first Earth Day was celebrated across the United States, an observance that would become a yearly event focused on raising and organizing environmental awareness.



The US Environmental Protection Agency is established

Created by President Richard M. Nixon, the EPA would become the primary federal agency charged with monitoring and regulating environmental health and quality in the United States.



The “Environmental Decade”

Beginning with the National Environmental Policy Act (NEPA) in 1970, which instituted environmental assessments and environmental impact statements in federal agency decision making, the decade would see a series of significant environmental regulations with direct implications for zoos and aquariums, including the Marine Mammal Protection Act (1972) and the Endangered Species Act (1973). The Convention on International Trade in Endangered Species (CITES), which entered into force in 1975, was another milestone in wildlife protection, a multilateral agreement to ensure that international trade does not imperil species in the wild.



The International Species Information System (ISIS) is established

A system designed to maintain zoo collection records, ISIS greatly improved zoo animal record keeping, established accurate heredity information on captive animals, and promoted more coordinated breeding programs among the zoos.



The National Zoo creates its Conservation and Research Center

Today, the Smithsonian Conservation Biology Institute (SCBI) conducts conservation breeding, research, and training programs at its location in Front Royal Virginia and at field research stations throughout the US and internationally. In 2008, the Smithsonian-Mason School of Conservation was established at SCBI enabling students at George Mason University to work with SCBI scientists.



The San Diego Zoo establishes the Center for Reproduction of Endangered Species

CRES (now the Institute for Conservation Research) is established in 1975 and a “Frozen Zoo” program is initiated, which results in the eventual accumulation of a vast amount of genetic material used for basic and applied biological research and the “genetic rescue” of threatened and endangered wildlife. [Photo: Dr. Oliver Ryder, Kleberg Endowed Director of Conservation Genetics at the San Diego Zoo Institute for Conservation Research.]




Captive Breeding Specialist Groups (CBSGs) established

Created by the IUCN (and eventually renamed “Conservation Breeding Specialist Group), CBSG was designed to connect in situ or field-based conservation projects with ex situ programs in zoos and aquariums. The organization has recently been renamed the “Conservation Planning Specialist Group” to reflect its expanded efforts in wildlife and wildland protection beyond breeding programs, coordinating with the Species Survival Commission (SSC) and advocating a “One Plan Approach” to conservation encompassing the full in situ-ex situ spectrum.



Species Survival Plans (SSP) begin

Developed by the Association of Zoos and Aquariums (AZA), SSPs are population management and conservation programs for specific taxa to enhance the genetic diversity and sustainability of populations and to promote animal survival in the wild. Starting with the Siberian tiger, golden lion tamarin, Asian wild horse and several other species, there are now nearly 500 SSP programs managed by AZA Taxon Advisory Groups.



The Monterey Bay Aquarium is established

Located in Monterey’s historic Cannery Row, the Monterey Bay Aquarium is distinguished by both its focus on the regional ecology of Monterey Bay and its well-regarded programs promoting ocean health, sustainability, and public education and inspiration.  Its long-running “Seafood Watch” program is one of the more well-known consumer advisory efforts focused on the consumption of sustainable seafood.



The California condor is declared extinct in the wild

The species, which was nearly lost by the 1980s, was recovered by a series of successful breeding programs at the Los Angeles Zoo and San Diego Wild Animal Park. These efforts led to the release of condors back into the wild beginning in the early 1990s. Today there are more than 400 condors soaring over sites in California, Arizona, and Baja Mexico.



The AZA Field Conservation Committee is formed

This body coordinates in situ with ex situ conservation efforts across the zoo community to enhance population sustainability and wildlife and habitat protection. Today, AZA accredited institutions are engaging in thousands of field-based projects in more than 120 countries around the globe. [Photo: The black-footed ferret, a species recovered by an intensive captive breeding and reintroduction program involving the US Fish and Wildlife Service and a number of zoos, including the National Zoo’s Smithsonian Conservation Biology Institute (SCBI), Cheyenne Mountain Zoo (CO), and the Phoenix Zoo.]



The World Zoo Conservation Strategy is published

This document, produced by (what is today) the World Association of Zoos and Aquariums and the IUCN, states that wildlife conservation “can only be achieved through the awareness of all nations, including all strata of their societies, their governments, other institutions and organizations. This also includes zoos and aquaria found in nearly every country of the world…”



Ethics on the Ark is published

Drawing together ethicists, wildlife biologists, and zoo leaders, the book was a landmark publication in the evaluation of zoos as emerging conservation organizations and especially in identifying the ethical challenges of balancing animal welfare with broader species and habitat protection goals as part of zoos’ mission to protect biodiversity.



Building a Future for Wildlife (World Zoo and Aquarium Conservation Strategy) is released

Produced by WAZA, the report updated the earlier 1993 strategy and deepened the organization’s commitment to animal conservation in the wild, championing a vision of “integrated conservation” linking ex situ and in situ organizations and projects while urging zoos and aquariums to meld “all aspects of their work with conservation activities.”



Amphibian Ark created (AArk)

Responding to the global amphibian extinction crisis, the AArk was formed as an umbrella organization to help coordinate the efforts of zoos and other ex situ institutions to conserve threatened amphibians around the world.  AArk institutions partner with field organizations to try to understand and mitigate threats to amphibian populations — and to enhance the chances of long-term species survival of species in the wild.



“Saving Animals from Extinction” Campaign is launched by the AZA


The Saving Animals from Extinction (SAFE) program targets 10 species in its public engagement and funding efforts, including the African penguin, Asian elephant, black rhinoceros, gorilla, sea turtles, and vaquita.  SAFE is intended to engage zoos and aquariums collaboratively with other conservationists and the public to save the targeted species by developing coordinated action plans and leveraging the collective expertise of AZA-accredited zoos and aquariums in these efforts.




Committing to Conservation is released

The latest World Zoo and Aquarium Conservation Strategy (updating earlier versions published in 1993 and 2005), explicitly defines conservation for zoological parks as “securing populations of species in natural habitats for the long term.”  It promotes the development of a “culture of conservation” across all organizational aspects of zoos and aquariums, increased funding for conservation projects and initiatives within the WAZA community, and the need to safeguard animal welfare alongside conservation priorities.



‘Toughie,” the last Rabbs’ fringe-limbed tree frog, dies at the Atlanta Botanical Garden

Named after the renowned zoologist and conservationist George Rabb, the species was devastated by the chytrid fungal epidemic striking amphibian populations around the globe.