About This Species
Lobster buoys dot the coast from New Jersey to Labrador, Canada, where the invertebrates thrive in the chilly water. American lobster can survive offshore as far south as North Carolina. But any farther south and they can reach a stress threshold, which can happen when temperatures exceed 68 degrees Fahrenheit. This can cause respiratory and immune system problems, make them more susceptible to shell disease and make it harder to reproduce.
Lobster are relatively slow-growing and can live for up to 50 years. Female lobster take about 10 years to mature, and carry their eggs on their underside for 9-11 months. Once hatched, lobster larvae move around through a combination of drift and swimming, ultimately settling in a location based on water temperature. The larvae eat phytoplankton and zooplankton, and seek shelter in rocks and vegetation.
A few decades ago, the lobster industry in New York and southern New England was booming. But in recent years, as the water temperature there has risen, it has bottomed out. Between 1996 and 2014, New York's registered lobster landings decreased by 97.7 percent. At the same time, Maine's industry has boomed. In 2014, Maine's lobster industry brought in $459.6 million, 81% of the entire industry earnings in New England.
Along the southern portion of the lobster's range, temperatures are already becoming inhospitable. In 1999, for instance, there was a massive lobster die-off in Long Island Sound after a long stretch of above-average water temperatures.
Globally, the ocean temperature has been rising at a rate of about 0.2 degrees Fahrenheit per decade since 1980. But that's not the case in the Gulf of Maine, where sea surface temperatures are rising nearly twice as fast as the rest of the world. Even under a low-emissions scenario, the Gulf of Maine will see 2 degrees Fahrenheit of temperature increase by the end of the century, and 4 degrees Fahrenheit under high emissions. As the temperature has risen, lobsters have moved farther north. Though the water is the Gulf of Maine is warming quickly, it remains colder than the areas along the southern portions of the American lobster's historical range.
The Lobster's Shifting Range
Since the late 1960s, the American lobster's range has already shifted substantially.
Rising temperatures in Maine's waters could cause problems for lobsters there too.
A 2013 study found that the American lobster has moved up the Northeast Coast at a rate of about 43 miles per decade between 1968 and 2011. Should the species continue at that rate, the bulk of the population would be in Canadian waters in the middle of the century.
Meanwhile, when it comes to lobster and climate change, there's more than just range shift to consider. As the ocean absorbs carbon dioxide it is becoming more acidic. The scientific findings are mixed on what this means for lobster. Some studies have found that ocean acidification is leading to thicker, stronger shells. But others have found that lobsters in an increasingly acidic ocean face the same threats as other shellfish--weaker shells that offer less protection.