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The third week of October ushers in another fleeting window for some of North America's most interesting wildlife spectacles.
From crabs scuttling across Florida's shores to grizzly bears retreating to their dens in Yellowstone, these natural events may unfold quickly. Miss this week, and you might have to wait another year.
In Florida's coastal regions, October marks the peak of the blue land crab migration. These vibrant crustaceans, some as wide as a dinner plate, emerge from inland burrows to spawn in the Atlantic under the cover of dusk.
Female crabs are marching through the roads to the sandy beaches in Florida to release their eggs in the ocean. Look for them along the shores of Miami-Dade and the Florida Keys.
The spawning season is almost over, ending by late October. The Florida Fish and Wildlife Conservation Commissionprohibits harvesting blue land crabs, disturbing egg-bearing females, or removing their eggs until October 31, when the season reopens.
Monterey Bay, California, hums with life in October as humpback whales still linger to lunge-feed on dense schools of anchovies and sardines.
From March to November, these giants make the bay their dining hall, often joined by dolphins and sea lions.
Whale-watching tours from Monterey or Moss Landing offer front-row seats to breaches and bubble-net feeding.
By late October, however, most humpbacks begin their migration to warmer waters, making this week and this month isthe last time to catch their acrobatics before they vanish.
The roughly 48,000-acre Alaska Chilkat Bald Eagle Preserve near Haines becomes a hotspot in October as 3,000 to 4,000 bald eagles gather to feast on late-season salmon runs.
From the Haines Highway, visitors can spot these majestic birds perched in cottonwoods or gliding low over the Chilkat River. Preserve officials recommend using designated pullouts as safe viewing stops.
Mid-October marks the early wave of arrivals, with numbers swelling through November.
Beaches in Florida State Parks became nurseries for sea turtle hatchlings from March until mid-October.
Tiny loggerheads, green turtles and leatherbacks break free from their sandy nests, scrambling toward the ocean under moonlight.
According to Florida State Parks, John D. MacArthur Beach State Park and Cayo Costa State Park are the most prominent locations for nesting. Two years ago, over 2,200 nests were recorded in John D. MacArthur Beach State Park alone.
Visit these protected beaches guided by conservation groups to witness this delicate journey. But hurry up, since the hatching season is almost over. These days and weeks are among the final opportunities this year to see the last of these tiny travelers.
In Yellowstone National Park, mid-October signals the start of grizzly bear denning season.
After months of hyperphagia, when bears are frantic foraging on berries, roots, and small mammals, they begin seeking high-elevation slopes to choose their winter dens.
In Yellowstone, grizzly bears often reuse natural cavities since digging and preparing a den can take up to seven days and require moving nearly one ton of material to make it comfortable.
Look for them in Lamar Valley or along the park's northern range. If bears still need to bulk up, they will remain active. By mid-November, most grizzlies will retreat to their dens, vanishing until spring.