Shoals Marine Research Lab

We have had colder than usual weather during the last few weeks. The temps have dropped into the 40’s, which hasn’t happened for some 2 decades locally. Water temps were low enough to kill some species of fish. On this outing we noted 7 juvenile jack sp. 6-9 inches, dead on the bottom, not decomposed. 1 hound fish, partially decomposed, 3 ft. 2 juvenile barracuda, not decomposed, 10-12 inches. There were no manatee observed. That would expected as they seek warmer waters during cold spells. The gulf shrimp have been much more prevalent this year, due to the low temps. We caught some for supper, however, it required braving windchills of 38 degrees. They are typically caught at night by dipnetting, and are frequently accompanied by slender brown eels, blue crabs, and ladyfish.

The cold-fronts that provide a tasty pan of peel and eat shrimp, are much shorter in their cyclical duration today. 30 years ago, the winds would take a week to complete a 350 degree compass swing. Now it is typically finished in less than 48 hours. This year it has been one cold front after another, more cycles, and of quicker duration. This is much, much different than the cold fronts of 30 years ago. The winds would swing slowly, often hanging out of the NW for a couple of days, before blowing chilly air through and returning to the balmier Easterly quadrant. In the past 5-6 years we have noticed that this change in pattern has become more pronounced, often with only a minor dip in air temps.

Solar observations: sitting in a sheltered area, the sun feels very strong. Very bright white. UV levels however, appear normal.

Water clarity: improved due to cold which causes algae decreases. Minor seagrass die-off.

Air quality: Clear, normal clouds and coloring. Sunsets typical. Dry.

This afternoon we took the dinghy across Tarpon Basin to check for manatees. This shallow lagoon is popular with the sea mammals, especially in the cold season. We also look for and collect plastic debris if seen, during these forays. Getting the dinghy ready we had a surprise when a large wood rat jumped out of the sail as it was unfurled. Some minor damage to sail was noted.

Weather: Mild, clear, unusually warm, 79 F

Water, clarity fair, 78 F

Winds, S 7 knots

We saw no manatees on the trip across the lagoon. Abandoned yacht is still present and intact. Nothing else noteworthy.

On the return trip, while closing the shore around sunset, we did see one manatee snout pop up to take a breath, only a few yards from our boat. Sailing is very quiet. No splashing, or engine sounds to annoy the owner of the snout. We returned to our mangrove berth after dark. Noted that the flashing marker light for the dinghy still works. Hopefully our SWRV will be back in service soon.

Plastic from human activity is frequently found, even in the remotest locations. It degrades very slowly and forms microplastic particles which disperse into the biosphere. These stray bits were dutifully collected and disposed of.

On this outing, we used the dinghy to conduct a survey on an area of mangoves to note which species were present. Glass minnows are a staple here. These greenish, transparent little fish are at the bottom of the food web. Several species of snapper were recorded, mostly Grey Snapper. Interestlingly, a new inhabitant of this ecosystem is the Green Iguana. These creatures are becoming endemic due to climate change and the lower incidence of cold weather which used to kill off any escaped pets each year. Now, they inhabit the mangrove canopy with impunity.

Last season we took our SWSV to Elliotts Key in Biscayne Bay to conduct marine life and general ecosystem assessments. We secured the SWSV in this location:

…And proceeded to spend two days observing the inhabitants.

Conch-Fully mature Queen Conch, 1, in deeper water. Appeared healthy.

Shovelhead Shark, 3, in shallow tidal creeks. Appeared healthy.

Smaller fish, Snapper Sp. not as numerous as we would like, around mangrove roots.

Larger apex predator fish, none observed in this location.

Misc. Shell life, crabs, very few.

Bird life, Several herons.

The water quality was moderate. Sea grass beds looked acceptable in most places. Concerning was the lack of small shell life on these flats. No juvenile conch were seen.

Lastly, very little litter or trash, plastic or debris was seen.

At the start of the third day, we moved the SWRV out of the tidal creek and returned south to Key Largo.

Our Main research platform has been undergoing an engine refit to replace the aging 2 cycle oil injected Evinrude with a smaller, lighter more modern engine. However, the shop has been shorthanded, and the only mechanic on duty has had a series of illnesses.

We have equipped the dinghy we built last season with a very functional mast and sail to better monitor the derelict boats abandoned in Tarpon Basin while we wait for the engine to be installed on our SWRV platform.

Seen here, in her mangove berth, is our smallest research platform. She currently benefits from donated anti-fouling paint, Thank you to our supporters!