Details

Published: 10 January 2025

IDNR Report

A colony of state-endangered crawfish frogs has successfully been reintroduced at Angel Mounds State Historic Site in Evansville, marking the first time in nearly 40 years the species has been seen at the site.

Starting in 2022, the multi-year conservation effort was a collaboration between the Indiana DNR Division of Fish & Wildlife and Angel Mounds.

“We are a multi-faceted site. It’s about the culture, history, and natural and environmental components that we can tap into, like this,” said Mike Linderman, site manager for Angel Mounds and southwest regional director for the Indiana State Museum and Historic Sites. “We’re helping an endangered species return to its natural habitat where it once thrived, that’s pretty exciting.”

With their spot pattern and loud croak, crawfish frogs are prairie-dwelling amphibians that spend much of their lives underground. The adult frogs, which can grow the size of a fist, rely on quality grassland habitat with high densities of crayfish burrows, which lends to their name. After sheltering in those burrows during the extreme weather months, the frogs emerge in the spring and relocate to nearby ponds to breed, leading to a chorus of croaking that can be heard more than a mile away.

A large population of crawfish frogs once thrived at Angel Mounds, potentially as far back as when Native Americans inhabited the site, until the mid-to late-1980s when the amphibians vanished suddenly and mysteriously, possibly triggered by an extended drought. Before the recovery project, the number of crawfish frogs in Evansville had dropped to zero, and the main threat to the species has been habitat loss due to land development.

“Indiana only has two robust crawfish frog populations remaining in the state,” said DNR Herpetologist Nate Engbrecht. “The recovery effort at Angel Mounds is somewhat unique for being a historic restoration project — a biological one — that aims to recover a historic component of the site that has been lost.”

A habitat suitability study conducted by DNR determined Angel Mounds has the ideal environmental conditions to support crawfish frogs. In particular, the analysis identified several small ponds in the northwest corner of the site that fill with water after each winter but dry out during the summer. The ponds were formed centuries ago from “borrow pits,” or large holes left after Native Americans built the mud wall at Angel Mounds.

In March, eight crawfish frog egg masses were collected from a large population in Greene County and relocated to the pond at Angel Mounds, where they were placed inside cages to protect the eggs as they developed. Engbrecht said the translocation process played out exactly as hoped, and within weeks, thousands of tadpoles filled the ponds. Engbrecht observed that the tadpoles began growing and developing legs, leading up to metamorphosis. Finally, following decades of absence, dozens of young spotted frogs began hopping by early July.

Crawfish frogs take two to three years to reach sexual maturity, meaning that the frogs that were moved to Angel Mounds this spring will not return to the pond from where they hatched to mate until 2026. In the meantime, the DNR plans to move additional egg masses to supplement the local population during the spring of 2025.

The Angel Mounds recovery project has also been supported by the Indianapolis Zoo, which provided grant funding for the habitat study, as well as Evansville resident and retired herpetologist Mike Lodato, who documented the Angel Mounds crawfish frog population crash in the 1980s.

More information about DNR’s work with crawfish frogs, including the ongoing project at Angel Mounds, is available through its website.

Details

Published: 23 December 2024

IDNR Report

Franklin’s ground squirrel

The Indiana Department of Natural Resources (DNR), The Nature Conservancy (TNC), and Purdue Fort Wayne (PFW) have teamed up to return Franklin’s ground squirrels to their native Indiana range, starting with a population at Kankakee Sands nature preserve last summer.

Franklin’s ground squirrels were once found throughout northwest Indiana’s prairies, but the species lost most of its habitat as agriculture advanced. It was listed as state endangered in 1993 after the number of counties the species occupied declined by nearly 45% from the previous census. Today, the squirrel’s environment has been fragmented, which exposes it to more negative environmental pressures including predation, vehicle strikes, and loss of genetic diversity.

That’s why the DNR, TNC, and PFW selected TNC’s Efroymson Prairie at Kankakee Sands to establish the first translocated population. The site’s short-grass prairie offers the space the ground squirrels need to spread out and thrive.

“The Nature Conservancy has been creating prairie habitat at Kankakee Sands for more than 25 years,” said Trevor Edmonson, project director for the site. “The bison herd we brought to the site in 2016 has greatly improved the prairie with their selective grazing habits. The time was right to bring in the Franklin’s ground squirrel to take advantage of the improved prairie.

“This was the goal of TNC’s Kankakee Sands restoration—to create a grassland conservation area where all prairie plants and animals can thrive.”

PFW researchers collected 25 Franklin’s ground squirrels from South Dakota. The squirrels underwent a vet inspection and a 30-day quarantine prior to entering acclimation enclosures and being released at Kankakee Sands. Some of the Franklin’s ground squirrels were equipped with GPS collars to monitor their movements, habitat selection, and survival.

This relocation is part of a larger effort to reestablish Franklin’s ground squirrels in their native range. All three partners are establishing small groups of Franklin’s ground squirrels on managed properties across the area and will monitor their survival in upcoming years.

“By establishing populations on large, managed properties, we can reduce negative environmental pressures and offer a path to recovery,” said Brad Westrich, DNR state mammalogist.

The partners will continue monitoring this first group of Franklin’s ground squirrels into next summer. The data from this first translocated population will inform future location choices of Franklin’s ground squirrels establishment efforts.

This work is just one project to help state endangered mammals in Indiana. To learn more, visit DNR’s mammals page by going to on.IN.gov/wildlife, clicking on “nongame and endangered wildlife” and then “mammals.” To donate to help fund similar efforts, please see on.IN.gov/nongamewildlifefund.

Details

Published: 12 December 2024

IDNR Report

Indiana’s Natural Resources Commission (NRC) has opened its second public comment period for proposed changes to allow the limited, regulated trapping of bobcats in designated counties.

In March, the Indiana General Assembly passed legislation (SEA 241-2024) directing the Indiana Department of Natural Resources (DNR), by July of 2025, to have rules in place for bobcat harvest.

This is the second of two comment periods to occur before the NRC votes on the proposed changes.

Proposed rule changes include:

• Establishing a bobcat trapping season in 40 southern Indiana counties, including a bag limit of one bobcat per trapper and a season quota of 250 bobcats.
• Allowing bobcats and their parts that are legally acquired to be sold.
• Allowing bobcats that are found dead to be kept by people with a permit.
• Adding bobcats to the list of species for which a game breeder’s license is required.

Research maintained by the DNR and Purdue University shows that the bobcat population in Indiana has expanded during the last two decades. This research can be reviewed at on.IN.gov/dfw-rule-changes. 

Bobcats have well-established populations in the 40 proposed counties, and analysis shows that this high-quality habitat can continue to support a healthy, sustainable bobcat population that can withstand a regulated harvest.

Public comments can be submitted at IN.gov/nrc/rules/rulemaking-docket by clicking on “Submit Comments Here” under the Bobcat Amendments rule. Comments can also be mailed to:
 Natural Resources Commission, Indiana Government Center, North100 North Senate Ave., Room N103, Indianapolis, IN 46204.
 
Please note that comments received during the first comment period (in person or online) will be included with comments received during this second comment period. Multiple comments given by the same person will only be counted as one comment by that person. 

The deadline for submitting public comments is Jan. 16, 2025. A public hearing will also be held on Jan. 16, 2025, between 5:30-8 p.m. ET at the Johnson County Fairgrounds (Scott Hall), 250 Fairgrounds St., Franklin, IN 46131. Interested members of the public can attend in person or online anytime during that timeframe. The public hearing will also be webcast live at IN.gov/nrc/rules/rulemaking-docket during the time of the public hearing, and viewers will be able to comment during the webcast. Sign up for updates at on.IN.gov/dfw-rule-changes.