As someone who has camped in national parks since the third grade, I can’t help but notice the blinding whiteness of the great outdoors. Everywhere I go, I see lots of other people who remind me of myself: aging and white.

My experience reflects a long-standing ethnicity gap: White visitors make up roughly 80 percent of all national park travelers, according to National Park Service visitation figures. Now, a proposed entrance-fee hike to $70 per car at 17 popular national parks — including such crown jewels as Yosemite, Yellowstone, Zion and the Grand Canyon, where entrance costs will jump from $30 for a weekly pass — could make these places even whiter.

If the price increases go into effect, all lower-income Americans stand to be priced out. Still, advocates say fee hikes could have an oversize impact on communities of color by creating a new disincentive for groups that have stayed away from, or felt discouraged from, visiting national parks, for reasons including fearful historical associations with wilderness areas and a perceived lack of cultural relevancy.

The most recent Park Service-commissioned demographic survey, from 2008 to 2009, showed stark differences among ethnic groups in terms of national park visitation: 78 percent white, 9 percent Hispanic, 7 percent black and 1 percent American Indian or Alaskan. Members of underrepresented groups pointed to the high cost of national parks. Forty-seven percent of Hispanic respondents, 54 percent of African American respondents and 59 percent of American Indian respondents said that hotel and food costs were too high in national parks, compared with just 33 percent of white respondents. And 32 percent of Hispanics, 25 percent of African Americans and 37 percent of American Indians said entrance fees were too high, compared with 20 percent of whites.

Finances are hardly the only factors in the low minority representation at national parks. In that same survey, a much larger proportion of black and Hispanic respondents said that the parks were too far away for them to visit more often. And there are cultural factors. Audrey Peterman, the Jamaican-born founder of an environmental consulting and publishing firm, has been an outspoken advocate for greater inclusiveness in the outdoors since 1995, when she and her husband, Frank, toured national parks starting in Acadia in Maine and working their way west to Yosemite. Before the trip, the Petermans’ friends questioned whether a black couple could be safe out there and urged them to take a gun.

Those worries reflected a history of racially motivated violence in the outdoors. In his book “Heading Out,” a history of camping, Terence Young noted that park administrators in the early 20th century followed a policy of “discouraging visits by African Americans, [who were], in the opinion of administration, ‘conspicuous . . . objected to by other visitors . . . [and] impossible to serve.” Virginia’s Shenandoah National Park, in the early 1940s, was up front about such exclusionary policies, with “separate but equal” camping, cottages and coffee shop.

Peterman embarked on her grand tour of national parks despite her friends’ historically motivated worries, but the lack of diversity offended her. “This is our country,” Peterman said to herself at the time. “We all pay taxes.” Peterman had a similar response when she heard about the proposed fee hikes. “It’s a step backward. Even beyond that, this proposal is within the context of a federal budget that plans to slash the budget of the National Park Service. This is more than just an issue of affordability.”

But affordability can make the difference between heading out and staying home. I saw plenty of evidence of this in 2014, when tagging along on an organized camping trip to the Everglades that upended the usual demographics of my trips to national parks. Except for a couple of white adult chaperons, the campers were African American and Latina teenage girls from low-income households in Miami. For most of the girls, this was their first camp-out and their first visit to a national park. Several of the girls had to persuade skeptical parents to let them attend. “My father just doesn’t get that I would want to do this,” one girl told me. “He told me: ‘Black people don’t camp. You can go in the back yard or watch the nature channel.’ ”

But the primary barrier to entry was financial; several campers told me they simply could not afford the expense of such an excursion when they factored in tents, sleeping bags and travel costs — not to mention park admission fees. The trip knocked aside such barriers, at least temporarily, because it was sponsored and co-organized by Inspiring Connections Outdoors, a Sierra Club affiliate that takes more than 14,000 youths, most of them from low-income families, from 52 U.S. cities on nature excursions, including national park camp-outs.

The girls did not share the safety concerns of their parents. On the second day, most showed no hesitation about boarding wobbly canoes to explore Nine Mile Pond, despite the presence of large alligators, including a big, fat one that was sunning itself on the shore near the place where they launched their boats.

On the final day, the girls learned about the environmental degradation of the Everglades and the introduction of invasive creatures decimating native animal populations. Several vowed to return to the Everglades again. But trip leader Karen Kerr worries that fewer young people will have such moments of discovery if national parks become cost-prohibitive. Everglades National Park is not one of the 17 parks targeted for possible entrance-fee increases, but Kerr said that even modest jumps in fees have made it harder for her ICO chapter to fund excursions over the years, because of the large number of support vehicles. Each driver must pay an entry fee.

The potential fee hike comes at a time when a number of groups, including Outdoor Afro, Hike Every Available Trail and Latino Outdoors, are working toward greater inclusiveness. Several have seen surges in membership in recent years. One reason is greater exposure, including the publicity of President Barack Obama’s barnstorming tour of western national parks in summer 2016. When Teresa Baker founded the African American Nature and Parks Experience in 2013, 500 group members visited national parks as part of an event held in the summer. This year, 2,000 members took part. “It surprises me how many people come up and tell me they were visiting a national park for the first time,” Baker said.

Baker said increased entrance fees at select parks will not stop her group’s momentum. But a number of parks targeted for fee increases are far from major cities. Such travelers already face high fuel costs just to get there. “If you have fees that add to those [travel] expenses, people will second-guess their travel plans,” she said.

Some have celebrated the idea of increasing park fees, given the record-high attendance at national parks last year and the need for a cash infusion to repair park infrastructure. Understandably, many park visitors crave more room to spread out in the best-loved parks and worry about aging roads, bridges, bathrooms and camping areas. But it’s important to remember that this popularity surge followed a long period of stasis, with Park Service administrators expressing concerns about a steep decline in per-capita visitation over the past two decades. Part of that stasis has been linked to “limited participation of minorities” traced to the 19th century, according to a study in the Annals of the Association of American Geographers, as well as pressing economic concerns. “Thinning out the crowds” might sound good, but the people forced to stay home could be the very ones the parks most need to attract — and with such steep hikes, there might not be much of a crowd remaining at all.