A whale in Boston Harbor could slow down your MBTA ferry commute. What to know

MBTA ferry commuters could experience delays heading to Boston today, but not for the reason you might think.

A juvenile humpback whale in Boston Harbor is causing delays on the Lynn, Hingham/Hull and Winthrop/Quincy ferries, the MBTA said Wednesday.

The delays are expected to last until Thursday, the agency said.

The MBTA announcement comes amid a busy summer of whale watching in the region. A humpback whale has been seen breaching in Boston Harbor and Dorchester Bay recently, and one crashed into a boat in New Hampshire last month.

Here's what to know about the ferry delays today.

Why is a whale causing delays for the MBTA ferry?

A juvenile humpback whale in Boston Harbor could cause delays on the MBTA ferry through Thursday, the agency said.

The setbacks are because of federal regulations that require boats to travel at 10 knots (about 11.5 miles per hour) or less in the vicinity of whales, according to the National Oceanic and Atmospheric Administration .

Ferries travel on average 13.5 knots (about 15.5 mph) but can go as fast as 36 knots (about 40 mph), according to data from the U.S. Department of Transportation ,

When does the MBTA expect ferry delays to end?

The MBTA said it expects delays to continue through Thursday.

Humpback whales generally spend the spring, summer and early fall months feeding in the North Atlantic Ocean before migrating south for the winter, according to NOAA .

More: A whale species not seen in MA waters for 20 years has been spotted twice. What to know

What kind of whales are in Boston Harbor?

Humpback whales aren't the only ones found in Boston Harbor and throughout New England during this time of year.

Some other species in the area include finback, minke and North Atlantic right whales.

This article originally appeared on Cape Cod Times: A whale in Boston Harbor could slow down your MBTA ferry commute. What to know