What are Fossils?
Fossils are the remains or traces of any organism preserved in the Earth's crust, and paleontology is the study of fossils. Through the careful collection and study of fossils, we can learn the stories of origins and endings-- life, death, and change-- played out over nearly 3.5 billion years of the Earth's 4.5 billion year history.

Why is Studying Fossils Important?
Scientists get clues from fossils left by everything from the tiniest bacteria to some of the largest creatures ever to roam the Earth, swim in its seas, or soar in its skies. These clues help us solve the fascinating riddles of how live on Earth evolved. Fossils illustrate how all forms of life are interdependent and affected by their environment. In addition, fossils are simply fun to study because of their natural beauty and the excitement, wonder, and understanding they evoke about life in ancient worlds lost in time, worlds that we can only imagine.

Where can I Collect Fossils?
All National Park Service, U.S. Fish and Wildlife Service, and Bureau of Reclamation lands are closed to casual collecting of fossils. It may be possible to casually collect reasonable amounts of plant and invertebrate specimens (small samples that are easily transportable by hand) without a permit on Bureau of Land Management (BLM) public lands. Certain BLM lands are also closed to casual collecting of fossils. You must check the land use plans or the local BLM office for these types of lands.

Remember, illegal collecting, including taking or damaging vertebrate fossils, is against the law. Your help is important to preserve America's natural heritage for future generations!

Thank you to BLM publication WO/GI-97/006+3032+REV11
A Park Service Paleontologist prepares a fossil for removal from the Monument.
An NPS paleontologist prepares a fossil for removal from the Monument.


What's Special about Hagerman Fossil Beds?

Hagerman Fossil Beds is nationally and internationally significant for its world-class paleontological resources. It includes the world's richest fossil deposits, in quality, quantity, and diversity, from the late Pliocene epoch. Many of its fossils represent the last vestiges of species that existed before the last Ice Age, the Pleistocene, and the earliest 'modern' flora and fauna.The Monument's paleontological resources are contained in a continuous, undisturbed stratigraphic record spanning at least 500,000 years. The fossils deposited here appear to represent an entire paleontological ecosystem with a variety of habitats such as wetland, riparian, and grassland savanna.

While best known for its fossil horses, Hagerman holds many titles, including

  • Largest accumulation of the single-toed horse, Equus simplicidens.
  • Largest accumulation of the giant otter, Satherium piscinarium.
  • North America's third most important site for Pliocene birds.
  • Numerous type species (first found and described here) such as: peccary (Platygonus pearcei), swan (Olor hibbardi), deer mouse (Peromyscus hagermanensis), vole (Ophiomys taylori), grison (Trigonictis cooki), pronghorn antelope (Ceratomeryx prenticei), a giant badger (Ferinestrix vorax), and large cat (Puma lacustris). A new species was just discovered last year and is currently being described for science!

Newly Discovered Species of Fossil River Otter

Brief History of Otters
Otters are members of the Mustelidae, a family that includes weasels and badgers. Otters first appeared in the Miocene of Europe and are represented by 13 living species. There are 6 species of otter found in the Americas today, including 4 river otters of the genus Lontra, the giant otter of South America, and the sea otter. Our new otter is at least 3.8 million years old and is the oldest example of the genus Lontra.

What’s in a name?
The genus name, Lontra, is used to show this otters relationship to American river otters. Its species name (weiri) distinguishes it from all other otters. Weiri is derived from the word “weir”, which is a river barrier that directs fish movement. The name reflects the otters’ diet of fish. It is also used here to honor Grateful Dead guitarist Bob Weir.

Why Is This Otter Important?
Ancestors of American otters entered North America from Eurasia by crossing the Bering Land Bridge. Paleontologists thought that this occurred in the Pleistocene, due to an absence of fossil American river otters in older deposits. Genetic studies of modern otters pointed to a much earlier origin, in the early Pliocene. Lontra weiri supports the genetic data. Advancements in paleontology are made with each new discovery as we slowly piece together the ancient history of life on earth!

Last updated: June 26, 2019

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Hagerman, ID 83332


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