Seal population rising in and around Saint John Harbour, study says | CBC News

There are more seals in and around Saint John Harbour than there were 30 years ago, and they’re staying year-round. 

Those are the findings of researchers who recently completed the first study of the seal population in the area since the early 1990s.

Although they don’t have hard numbers, “the numbers that we counted on rocks were higher than the number that they had counted in the 90s,” said Shauna Sands, the lead author and former conservation co-ordinator with the Atlantic Coastal Action Program in Saint John.

From December 2018 until March 2023, Sands and her team counted seals at six different “haul-out sites,” rocky safe havens where seals are known to gather to rest, sunbathe, or hide from predators.

Every two weeks at low tide, researchers would use spotting scopes and sometimes drones to count the number of seals on those rocks. Sands says she and her team modelled their study on the last one that was completed in 1991 so that results would be comparable.

The team used the same locations as well, including Shag Rocks, Island Bar and Round Reef in the harbour. They also conducted counts at Dog Rocks, near the Irving Nature Park, the Musquash Ledges near Black Beach, and Sea Dog Cove on the Kennebecasis River. 

“When we did our research, we found there were seals all the time,” said Sands. “Their numbers would decrease in certain times of the year, but they were always there.”

She said it was previously believed seals would move south each year, likely to the Gulf of Maine, where food was more abundant. But now it appears there’s enough to maintain the animals all year.

She said population numbers were at their highest in the spring months at most of the research sites, with the lowest numbers recorded in the fall. 

WATCH | On the rocks — researchers count seals in Saint John Harbour using spotting scopes and drones:

How are the seals doing in Saint John Harbour?

Over the last five years, a seal count has been happening in Saint John Harbour to check on the size of the population. 

Roxanne MacKinnon, executive director of the Atlantic Coastal Action Program, said the seal population appears healthy and that gives scientists a good indication that their prey populations are also doing well. 

“They are a large marine mammal, so they do feed predominantly on fish and invertebrates like squid,” said MacKinnon.

“So, by having a healthy seal population, we basically infer that there’s a healthy fish population to support that.” 

While the population is estimated to be in the hundreds, MacKinnon says the study wasn’t designed to give a specific number on how many seals inhabit the harbour, but instead it provides data that can be compared to previous studies to ascertain wether the population appears to be growing, shrinking, or plateauing.

“Getting down to the actual number was kind of out of the feasibility of the study just because we can’t be everywhere,” said MacKinnon.

“We can’t see all the seals at the same time, but … on an observation day, we are seeing seals into the hundreds. So we know there’s at least hundreds of seals kicking around.”

A surprising species 

Researchers know that harbour seals are the most common type in the area, but during this study they were caught off guard by another seal species that kept popping up.

“We were surprised by the amount of grey seals that were out in our harbour, said Sands. “We did a few boat surveys and we did find that there were a lot of grey seals hauled out.” 

She says the biologists who completed the former study didn’t see that many. 

Sands says that grey seals, which are larger, haven’t been studied extensively in the harbour, so it’s unknown if their population is growing, but she expects that will be studied in a future project.