WASHINGTON — Advocates of trophy hunting, and even the United States government, have long justified the killing of protected wildlife in Africa by saying that taxes and fees from the hunts help pay for larger conservation efforts.

But a new report by the Democratic staff of the House Natural Resources Committee challenges those claims, finding little evidence that the money is being used to help threatened species, mostly because of rampant corruption in some countries and poorly managed wildlife programs. It concludes that trophy hunting may be contributing to the extinction of certain animals.

It has been almost a year since an American hunter killed a beloved lion named Cecil in Zimbabwe, setting off an international debate over sport hunting and widespread anger on the internet. Since then, the Obama administration has placed lions in Africa under the protection of the Endangered Species Act, France has banned the import of lion trophies, and more than 40 airlines have said they will no longer transport hunting trophies.

The 25-page House report, called “Missing the Mark,” says that while poaching remains the gravest threat to animals like lions, rhinoceroses and leopards, “trophy hunting also removes a significant number of animals from these rapidly declining populations.”