The fringes of the grizzly range, van Manen said, are typically occupied by dispersing young boar bruins. Typically, he said, there's a multiyear lag before female bears will fill in territories already settled by males.
"Given what we've seen in the Wind River Range [with male bears], I wouldn't be surprised if females were close behind within a matter of five years," van Manen said.
The Wind River Range is located in west-central Wyoming, southeast of Yellowstone.
Van Manen anticipated continued expansion into the Wyoming Range, a livestock-dense landscape where he said bear conflicts with livestock and humans are inevitable.
"Bears are simply entering a landscape where the potential for conflict is greater," he said.
Twenty-seven percent of grizzly range within the region is now outside a "demographic monitoring area" where bear numbers are assessed annually.
The population of grizzlies within the monitoring area has fallen for two consecutive years, from about 750 animals to 690.
But van Manen noted that grizzly numbers outside the monitoring area are not counted and said he is confident the population is now at the highest point in decades.
"Since listing, there's no doubt that we are now at a point that we have the largest population size," he told the Jackson Hole News and Guide.
Center for Biological Diversity attorney Andrea Santarsieri said that he was concerned by the decline in grizzly numbers, and worried that hunting could soon occur near the Yellowstone and Grand Teton park boundaries if states gain management authority.
"We are made to believe that hunting and management are synonymous," Santarsieri said. "I would say that they're not. Agencies here are touting a recovered population, and we got where we are today without hunting."
A final rule to delist the Yellowstone-area grizzly bear as a federally protected endangered species will be released as early as June, federal officials said at the meeting.