Look at the Fishies!

From Fish to Fossils

The bottom dwelling fish in Florissant were able to live in the poor conditions of the ancient lake. Diatom mats, or single-celled algae that have dense cell walls easily sank to the bottom of the lake. These microogranisms along with clay, silt, and volcanic ash created alternating layers at the lake bottom. When fish died, their skeletons would sink and become compressed in between the layers.The fish skeletons became preserved or created impressions in the rock. Finer details such as fish scales became carbonized, or turned into carbon in the rock.

 

Paper shale consists of thin alternating layers of clay, silt, volcanic ash and single-celled algae called diatoms. Shale is a sedimentary rock which means that it’s made up of smaller fragments of other rocks, sediments, and organic material.

NPS

 

Let's catch some fish!

Before we begin, read these basic fishing tips:

For this activity, you'll be virtually fishing.

1. Use the sliders below to reel in and reveal your catch and its fossilized version.
2. Read about each fish using the drop-downs.

Note: the following tips are for when you actually go fishing in-person.

• Keep in mind that many places to fish require a fishing license and that you have to follow fishing rules and regulations.
• You've scouted out a great spot from the shore. Good eye!
• Wear a life jacket!
• Make sure an adult is handling the fish hook, which has barbs.
• Be patient!

Now, cast your fishing line into the water and wait until you get a bite on your line.

 

Let's go fishing on the lake!

NPS / Karen Ceballos & Astrid Garcia

 

You notice a small shadow moving below the surface and slowly start to approach your lure. Suddenly, you feel a bite and you start to tug and reel the fish in. Move the slider to the right to see your catch.

Move the slider to the left to view the fossilized ancient fish. Read about the fish in the drop-down below.

 

Left image
Credit: NPS Photo

Right image
Credit: NPS Graphic

  What'd you catch?

Sucker (Amyzon)
These are the most diverse fish found at Florissant, with fossils of three species part of the now extinct genus Amyzon found here. This fish likely reproduced in tributary streams, which are streams that feed into the lake. 

The suckers were bottom dwelling fish that would feed on the oozes at the bottom of the lake. This ooze consisted of algae, debris, and insect larvae. The suckers recycled many important nutrients in the lake. 

 

You turn to see another few shadows lurking beneath the lake's surface. After casting your line, you wait patiently. You begin to feel another tug in the water and you pull and begin reeling the fish in. Move the slider to the left to see your catch.

Move the slider to the right to view the fossilized ancient fish. Read about the fish in the drop-down below.

 

Left image
Credit: NPS Graphic

Right image
Credit: NPS Photo

  What'd you catch?

Pirate Perch (Trichophanes)
The pirate perch are not considered true perches. The pirate perch of Florissant are part of the extinct genus Trichophanes. This ancient fish likely fed on aquatic insects and smaller fish, but would have been prey to the larger bowfin.

Several well preserved specimens of this fish have been found here. This type of fish shares some similarities to the trout perch. This modern species is restricted to freshwater ponds and lakes in North America.   
 

 

After you're done virtually fishing, select where you want to go next.

Where to next?

1. Go back to the lake.
2. Revisit the Eocene.
3. Return to the present.