A changing of the guard, of sorts, is about to happen.
In less than a month, the sandhill cranes will begin returning to the Merced National Wildlife Refuge (NWR) and other refuges of the San Luis NWR Complex. For many years the first sandhill cranes have arrived at their wintering grounds from Sept. 12 to 15.
For some people, the return of the cranes is considered the official start of the best time to view waterfowl and other birds at local refuges and wildlife areas.
But waiting a month to breakout the binoculars isn’t necessary since in August young Swainson’s hawks have fledged and soon will be gathering with their kind to form “kettles” over valley grasslands. Kettles are large swirling, circling flocks of birds rising into the sky as they search for thermals to help them gain altitude and conserve energy and strength as they set off on their seasonal migration.
The formation of kettles also serves as a form of communication between individuals, sort of an announcement to others of their imminent departure. In the case of the Swainson’s hawks, they will be departing for their wintering grounds in Argentina.
Kettles are most often observed among hawk species, but other soaring birds form kettles as well, including the American white pelican, a waterbird species that winters here in the wetlands of the San Joaquin Valley.
Soon, irrigated agricultural land, like pastures, will attract white-faced ibis and long-billed curlews returning from their breeding grounds in places like eastern Oregon, Idaho, Montana and Wyoming.
In addition to the sandhill cranes, September will see the return of some migratory duck species like cinnamon teal. Various songbird species will also be migrating south and can be seen in riparian areas like Salt Slough, the San Luis NWR and the Pelican Nature Trail at the San Joaquin River NWR.
Speaking of the San Joaquin River NWR, come October, the once-endangered Aleutian cackling geese will be returning to their core wintering grounds there.
Throughout October, more and more ducks will arrive on their wintering grounds throughout the wildlife refuge complex as the wetland basins continue to flood providing habitat for wintering dabbling and diving ducks, as well as geese, shorebirds and the sandhill cranes that roost in the wetlands at night.
In November and December, as one of the main attractions at the Merced NWR, the snow and Ross’s geese arrive. By the time their numbers peak, the white geese will provide spectacular sights and sounds for refuge visitors as 60,000 or more geese roost in the wetlands and forage in the upland grasslands of the wildlife refuge.
Another winter resident of the wildlife refuges arrives in December, though in much smaller numbers – the tundra swans. Most of the swans can usually be seen in the Sousa Marsh area of the San Luis NWR, but they are also seen at Merced and San Joaquin River NWRs.
A popular sight for wildlife observers at the refuges is the increased diversity of raptors in the winter. During the summer season, there are seven or eight species of raptors present, but during the winter season, the diversity increases to about 16 species.
The best time of year to view wildlife at the local refuges is fall, winter, and early spring. The best time of day to view wildlife is early morning, the earlier the better, and late afternoon to early evening, an hour or two before sundown. In the morning, wildlife is frantically active as they search for food to break their night-long fast.
At the end of the day, they’re nearly as active to grab that final mouthful before settling in for the night. Early morning and late afternoon/early evening also permit wildlife to avoid the harsh light and higher temperatures of mid-day, as well as avoiding some predators that may be more active during those hours.
When driving along the auto tour routes of the wildlife refuges visitors are encouraged to stop and look but they should remain in their vehicle. Wildlife have become accustomed to the presence of slow-moving vehicles moving through their habitat. What scares them is when vehicles stop, and people get out accompanied by the loud sounds of slamming doors and human voices.
When walking along nature trails, visitors should keep their voices low and avoid running or other quick movements. It’s also best to leave one’s pets at home. Sometimes, just the scent of a domestic dog is enough to keep wildlife in hiding and alter their natural behaviors.
Some tools to help make wildlife viewing more rewarding include a pair of binoculars or a spotting scope. These items allow you to get great views of wildlife, while maintaining your distance and, therefore not disturbing them or altering their natural behaviors.
In addition to binoculars and spotting scopes, consider including a camera and a notebook or journal in your wildlife-watching gear. It’s also a good idea to take along sunscreen as well as insect repellant, as the mosquitos are making their presence known this time of year.
If you would like to participate in a guided wildlife observing activity, mark your calendar for Saturday, Oct. 12, when the San Luis NWR will host Tule Elk Day 2024. The free event will begin at 8 a.m. and go until noon. No registration is required.
Activities planned for the day include guided hayride tours through the tule elk habitat, a youth archery range, a wildlife photography presentation, a tractor display, and various kids’ activities.
The Merced National Wildlife Refuge (located at 7430 West Sandy Mush Road), the San Luis National Wildlife Refuge and the San Joaquin River National Wildlife Refuge comprise the San Luis National Wildlife Refuge Complex. Its headquarters and visitor center are located just north of Los Banos off Highway 165 at 7376 South Wolfsen Road.
The refuges are open to visitors daily from one half-hour before sunrise to one half-hour after sunset. The visitor center is open Monday through Friday except federal holidays from 8 a.m. to 4:30 p.m.
For more information, call the refuge visitor center at 209-826-3508, ext. 127 or check out the upcoming events on the website at fws.gov/refuge/san-luis.
