NEWPORT, R.I. — The Audubon Society of Rhode Island held its second Bird Symposium on Sunday, inviting dozens of experts from around New England to discuss the latest ornithological research and solutions for protecting species around the region and beyond.

Audubon jam-packed the event’s schedule with lectures about songs of swamp sparrows to the impacts of artificial light on bird migration.

Bird-science heavyweights Carl Safina, author of “Alfie & Me: What Owls Know, What Humans Believe,” and Harvard professor Scott Edwards book-ended the conference. Safina spoke about his book and the pressures facing birds, while Edwards highlighted the need for diversity in ornithology and the natural and sociological themes of his lauded cross-country bicycle trip.

Organizers recorded all of the Feb. 3 lectures, which will soon be available on AudubonRI’s YouTube channel, but in the meantime, here’s four takeaways from the day’s events:

Birds are struggling — in Rhode Island and elsewhere.

The number 3 billion got thrown around a lot, in reference to how many birds have been lost out of the net population since 1970.

Many of the species’ losses include American sparrows, old world sparrows, blackbirds, and larks, according to University of Rhode Island professor Peter Paton. Paton has studied birds in Kingston since the 1990s, picking up on the work of the late Doug Kraus, who started the study in 1960.

Records from both scientists show decreases in many species’ presence at their research site near the university, some as much as 70% or 80%.

“It’s not a pleasant story,” Paton said.

But it’s not fruitless, he added. Actions as simple as keeping cats indoors, adding decals to large windows, and planting native vegetation can all prevent bird mortality.

Renewable energy could impact birds, and people are trying to find ways to mitigate that.

Shilo Felton, a senior scientist at the Renewable Energy Wildlife Institute, gave a presentation on ways the solar and wind industries could avoid and reduce their impacts on birds and bats.

“Nothing’s a silver bullet,” she said. But she noted there are a lot of best practices that can be implemented and innovations that are in the works.

Felton grouped actions companies can take into three categories: avoid, minimize, and compensate.

Avoidance techniques come in mostly during decisions over where to site solar or wind projects. She gave the example of the decision to exclude Nantucket Shoals — the shelf off the southern coast of Nantucket, Mass. — from wind development because it is an important bird habitat.

After developments have a location, minimizing impact through natural vegetation, in the case of ground-mounted solar arrays, to maintain some habitat, or implementing an operational pause, in the case of turbines, to avoid hitting birds and bats during their most active periods, can help reduce bird takes.

The compensation — which Felton said could also be referred to as “restore” or “offset” — is usually regulated, formula-based, and focused on reducing takes of species in other situations, like having a wind company contribute to a lead mitigation fund to prevent more lead-related eagle takes.

Saltmarsh sparrows are a sexy (and a little sad) bird to study in the ornithology world.

Four different presentations from three different states focused entirely on saltmarsh sparrows, a little golden-brown bird that nests in marsh grasses.

Climate change is threatening salt marshes around New England and the sparrows named after them.

The sparrows are “living on the edge,” in more ways than one, Grace McCullough, a master’s student at the University of New Hampshire who studies the birds, said.

They nest in grasses on the marsh and need about 26 days without tidal flooding for eggs to become fledglings. But as high tides move farther and farther up the shore as sea levels rise, there are fewer suitable locations to raise young.

The U.S. Fish & Wildlife Service considers the birds “vulnerable.”

In the course of her study, McCullough found maintaining elevation is pivotal to the species’ survival. “A few centimeters can make the difference between a successful nest and a failed nest,” she said.

There are some success stories.

“I have good news,” Lincoln Dark, a Rhode Island native and AudubonRI volunteer, said to start his talk, “which is something you might not have heard a lot of today.”

Dark works as the coordinator for the organization’s surveys of ospreys, a bird he said is making a comeback.

In the 1970s, the prevalent use of DDT had almost wiped out the shore raptor in Rhode Island. Poisoning and thinning shells caused by the chemical left only 13 mating pairs in the state that year.

Today, since the prohibition of DDT, ospreys have come back, and more than 200 pairs now live along the Ocean State’s coast.

Dark said there is more to study, like temperatures impacts on the birds, and that AudubonRI is always looking for more volunteers to monitor nests.