A three-year study in northeastern Illinois and northwestern Indiana found that – even at small scales – emergent wetlands or ponds support many wetland bird species. The study also found that, at least in the years surveyed, the level of urbanization had little effect on most of the studied species’ use of such sites, provided the right kinds of habitat were available.
Although it still feels like beach weather across much of North America, billions of birds have started taking wing for one of nature’s great spectacles: fall migration. Birds fly south from the northern U.S. and Canada to wintering grounds in the southern U.S., Caribbean and Latin America, sometimes covering thousands of miles. Other birds leave temperate Eurasia for Africa, tropical Asia or Australia.
Using observation records and data collected through bird banding, 20th-century ornithologists roughly mapped general migration routes and timing for most migratory species. Later, using radar at airports and weather stations, they discovered how weather and other factors affect when birds migrate and how high they fly.
Now, scientists are setting up a global network of receiver stations called the Motus Network, which currently has 1,500 receivers in 31 countries. Each receiver constantly records the presence of any birds or other animals within a nine-mile (15-kilometer) radius that scientists have fitted with small, lightweight radio transmitters, and shares the data online. The network will become increasingly useful for understanding bird migration as more receiver stations become active along migration tracks.
Tracking individual birds via satellite
Three new technologies are rapidly expanding what we know about bird migration. The first is satellite telemetry of bird movement. Researchers fit birds with small solar-powered transmitters, which send data on the birds’ locations to a satellite and then on to a scientist’s office computer. The scientist can learn where a bird is, the route it took to get there and how fast it travels.
For example, the bar-tailed godwit, a pigeon-sized shorebird, breeds in Alaska and then migrates to New Zealand. Satellite transmitters show that godwits often fly nonstop from Alaska to New Zealand. Recently, a godwit set the record for the longest nonstop flight by a land bird: 8,100 miles (13,000 kilometers) in 10 days, from Alaska to Australia.
Satellite telemetry studies show how much individual birds, even those from the same breeding location, vary in their migratory behavior. Individual differences in migratory behavior are probably due to differences in physical condition, learning, experience and personal preferences.
Another shorebird, the whimbrel, also makes a phenomenally long journey over the ocean. Satellite telemetry has shown that some whimbrels travel from northwest Canada, across the North American continent to Canada’s east coast, then set off over the Atlantic Ocean on a 3,400-mile (5,400-kilometer), six-day nonstop flight to the coast of Brazil. In total, they may travel 6,800 miles (11,000 kilometers).
Many birds are too small to carry a satellite transmitter. Given the energetic effort required for migration, a device must weigh less than 5% of a bird’s body weight, and many migratory songbirds weigh under 0.7 ounces (20 grams).
Birds carrying geologgers must be recaptured to download the data. That means the bird must survive a migration round trip and return to the same place where it was first captured and tagged. Amazingly, many geologger-tagged small birds do.
Geologgers have shown that Blackpoll warblers – small songbirds that breed in the boreal forests of North America – fly long distances over the Atlantic in fall, heading to the Amazon basin. Birds breeding in eastern North America head out over the Atlantic in maritime Canada or the northeastern U.S. and make a 60-hour, nonstop, 1,500-mile (2,500-kilometer) flight to the Greater Antilles. There they rest and recuperate, then continue across the Caribbean to South America.
Blackpolls breeding in Alaska fly across the North American continent before leaving shore on the Atlantic coast and flying to South America. In total, they journey 6,600 miles (10,700 kilometers) over 60 days.
Even more amazing, geologgers show that another small songbird, the northern wheatear, migrates from North America to sub-Saharan Africa. Wheatears that breed in Alaska fly 9,100 miles (14,600 kilometers) across Asia to East Africa, taking three months to do so. Those breeding in eastern Canada journey 4,600 miles (7,400 kilometers) across the Atlantic to Europe and then on to West Africa – including a 2,100-mile (3,400-kilometer), four-day nonstop overwater flight.
Recording birds’ night migration calls
Two hours after sunset in fall, I like to sit outside and listen to birds migrating overhead. Most birds migrate at night, and many give a species-specific “chit,” “zeep” or other call-note while in flight. The calls may serve to keep migrating flocks together, including different species heading to the same destination.
Ornithologists are using automated passive acoustic recording to study these nocturnal calls and identify the species or group of related species that make each sound. The technology is a microphone directed at the sky, connected to a computer that continuously records the sound stream and is aided by sound recognition software. Sometimes it reveals migrants overhead that are rarely seen on the ground.
Nick Kachala, an honors student in my lab, set up recording units on three university properties in the fall of 2021. One of the most common migrants recorded was the gray-cheeked thrush, a shy bird of the northern boreal forest that is rarely seen in the northeast U.S. during fall migration. He also detected the dickcissel, a grassland bird that I have never seen in our area.
Radar monitoring indicates that the number of North American migratory birds declined by 14% between 2007 and 2017. There probably are multiple causes, but habitat loss is likely the principal culprit.
Effective conservation measures require knowing where and how birds migrate, and what dangers they face during migration. Ornithologists, using these new technologies, are learning things that will help to stop and reverse the global decline in migratory birds.
Armadillos, with their shells and long snouts, are often found waddling through the Texas desert.
But over the past decade, the animals have started to migrate into Illinois — and now they’re overwhelming the southern part of the state and showing up as far north as Peoria and Springfield. Experts say the shift is partly because of wetter summers and milder winters.
Fresh research shows that high emissions scenarios place the vast majority of ocean life at ‘high’ or ‘critical’ risk, with implications for the economic wellbeing of costal economies and future food security.
Recent Clemson University Ph.D. graduate Rhett Rautsaw wanted to explore whether the evolutionary theory of character displacement — when two species live in the same area and evolve to avoid competing over resources such as food — extended to pit viper venom.
There was one problem. To study competition, Rautsaw had to know where each pit viper species lived, and there wasn’t a comprehensive source of that information readily available.
Rautsaw created VenomMaps, a database and web application containing updated distribution maps and niche models for all 158 pit viper species living in North, Central and South America. Pit vipers are a group of venomous snakes, including rattlesnakes, copperheads and cottonmouths. While Rautsaw needed the information for his evolutionary biology research, the maps provide vital information for conservation efforts, citizen scientists and medical professionals.
The newfound interest in bird-watching and bird photography might be great for human mental health and social distancing. But scientists have been concerned about how all this up-close observation is affecting birds in their nests.
New research finds they didn’t have to worry as much as they thought.
Survey and Assessment of Large-River fishes in Illinois (commonly referred to as LTEF for Long Term Electrofishing) has been tracking changes in the Illinois River fish community, water quality and habitat since 1957. Over the years, funding and program leadership has periodically changed, but monitoring has always been conducted by Illinois Natural History Survey (INHS) biologists out of Havana, Illinois, currently at the Illinois River Biological Station (IRBS). Since 1989, funding for the LTEF program is provided by the Illinois Department of Natural Resources/U.S. Fish and Wildlife Service Federal Aid in Sportfish Restoration program.
Birds from every continent except Antarctica have been photographed nesting or tangled in our rubbish. Photos were submitted by people from all over the world to an online project called Birds and Debris. The scientists running the project say they see birds ensnared – or nesting – in everything from rope and fishing line to balloon ribbon and a flip-flop. Nearly a quarter of the photographs show birds nesting or entangled in disposable face masks. The focus of the project is on capturing the impact of waste – particularly plastic pollution – on the avian world.
The McKinney fire began on July 29 and has exploded to more than 60,000 acres, killing four people and becoming California’s largest fire so far this year. According to local tribal leaders, the fire has also led to the mass fish kill in the Klamath River, which runs for more than 250 miles from southern Oregon, through Northern California and out to the Pacific Ocean.