A recent surge of manatee sightings in Dog River has incited wonder and curiosity among local residents. One creek in particular, Moore Creek, has been frequented by the lumbering sea cows.
According to Ruth Carmichael, senior marine scientist at the Dauphin Island Sea Lab and associate professor of marine sciences at the University of South Alabama, manatees have historically made their way to Mobile Bay and its tributaries.
“The animals’ being here isn’t new … We’ve had manatees even in the fossil record here in the northern Gulf … We know just from [the Mobile Manatee Sighting Network] and by talking to people in Mobile that we have documented evidence of animals coming here since the early 1900s.”
Although manatee activity and migration in the Mobile Bay region is not a recent phenomenon, organized study of it is.
“We actually got involved with manatees when I got here in 2007 … At that time, there was no formal study of manatees in our area at all. In fact, the state of Alabama considered and actually listed manatees as accidental here.”
Carmichael and her colleagues quickly learned how great a misconception that actually was.
“Not only are they not accidental, but as a part of our research, we now know that these animals are coming here regularly and that some portion of the population comes back year after year … We have animals that we know come regularly from as far away as Tampa. It looks like, from our data, Mobile Bay is a migratory stopover for many animals, and it’s actually a migratory endpoint for some.”
One of the most significant problems for Carmichael and her colleagues is determining whether or not this increase in sightings corresponds to an increase in migration.
“Are there more animals coming here or are we just noticing them? I actually do think at this point we have more animals coming here and staying longer than we did in the past and that can be due to several things.”
The first reason, according to Carmichael, for a possible spike in manatee migration is an increase in the overall population.
“When we started our program, the population of species was estimated at 3,000. That number has increased to between 5,000 and 6,000 in the last few years.”
Manatees are federally listed as an endangered species, which means recovery efforts are working.
“We know that there has been some documented recovery of the manatee population in Florida and that’s a great thing, but you have to figure that while the populations are increasing, habitats are not. It just makes sense that if you have more animals, they’re going to need to spread out to survive.”
Some researchers believe another reason for a broader manatee migration is climate change.
“Change is change. I guess whether or not it is positive depends on your perspective,” Carmichael said. “We’ve seen this with a lot of other animals that are changing distributions latitudinally because of climate change.”
The Mobile Bay region provides manatees with the warm climate and vegetation they enjoy eating.
“Pretty much all that stuff that mucks up your prop when you’re up in Dog River — that’s manatee food,” Carmichael explained. “The dogma of course is that they eat seagrasses, but the truth is that they eat any kind of submerged vegetation … they’re actually really great for cleaning up all that excess vegetation we get in the upper reaches of the rivers.”
Seagrass is not the only kind of vegetation manatees eat.
“They’ll even eat grass off of people’s lawns,” Carmichael said. “If there’s overhanging tree branches, they will reach up, because their lips are prehensile and they can wrap them around the branches and denude it of leaves.”
As for Moore Creek, there doesn’t seem to be anything particularly unique about its ecosystem drawing the manatees.
“These animals seem to have certain places that will be very popular one particular year, and then they may or may not even go back to that same specific spot next year. Some of it seems to have to do with salinity changes, how much discharge we get, because they certainly follow freshwater pulses … even their preferences of specific vegetation will change from one year to the next, and no one fully understands what exactly drives those specific favorites. A single animal might one year prefer a certain type of plant and then the next year barely touch it.”
When asked what precautions one should take when interacting with manatees, Carmichael said to, first and foremost, give them space.
“We encourage people to watch the animals, we just encourage them to do it from at least 100 feet away. It’s important to keep in mind that they are wildlife just like any other kind of wildlife, so it’s not a good idea to get in the water with them. There are places in Florida where you can do that in a supervised way. We don’t have that here and it’s technically not legal for people to do that.”
One should also be careful not to strike a manatee while navigating through narrow waterways.
“The major cause of mortality for manatees is boat strikes. We are very fortunate here in Alabama in that we have no known boat-related mortality. If you do think you might have hit an animal, please let us know, because we can at least go out and check on the animal and make sure everything’s all right.”
One should also notify the Mobile Manatee Sighting Network by phone at 1-866-493-5803 or by email at [email protected] of any manatees one has seen.
“[Sightings] all go into a permanent database that helps us track these animals, get some sense of the numbers that are coming here, how long they are staying here.”
Summarizing the role of the average citizen in the protection of the manatees, Carmichael recommended a variety of constructive actions.
“Be aware, boat with caution. If you do see an animal or you think you do, boat safely, cut your engine, observe them safely, take pictures and report your sightings as soon as you can, and please don’t, under any circumstances, feed or get in the water with the animals.”