Nothing Fishy Going On: Mandahl Feb. 2021 Summary, Part 2
Hi!
Continuing with the February 2021 summary of the Mandahl Bay, St. Thomas, Virgin Islands Eco-system:
Part 2
Published March 22, 2021, Karl Callwood
With the visible presence of birds loosely catalogued as ‘fly-catchers and seed-eaters’ on the rise, we can also look to the ocean as a cause for their increased bravado.
Normally confined to tree cover, and making only short, fast darting flights across the open, the recent bravado of these birds invites inquiry. True, this is courtship and mating season, which causes us to notice birds more. Their calls are louder, more frequent and more complex. Distracting courtship dances and
fights are taking place. Avians are foraging for nesting materials and can been seen in flight carrying twigs many times their body length. The season calls for riskier and more open behavior in hopes of successfully attracting the best mate.
Yet long-term observation of the Mandahl Bay Eco-system tells us that this season normally presents with a much greater sighting of these birds throughout the arena. Most are not migratory and have a year-round presence. So, what our continued monitoring and bird count of the area tells us is that there is not an increased number of birds … only an increase in open-area sightings!
As stated in Part 1: “Advent of the Seed-eaters and Fly-catchers: February 2021 Summaries”, the drastic reduction of bait fish species, and the subsequent emigration of the large sea and pelagic birds that feed on them, has created more air space for the smaller birds to enjoy. There has also been a resulting increase in birds-of-prey cutting through the lagoon chasing the newly visible seed-eaters and fly-catchers. We’ll get to that in later Parts.
Today, we’ll look at the visible fish presence as we search for the bait fish that famously drives the sports fishing industry to the lagoon.
Mandahl has a popular … and free … commodity that benefits a large sector of the island’s marine economy. Mandahl’s silvery bait fish species allow commercial fishermen to serve us pelagic staples like tunas and mackerals (Bonito, Kingfish, etc.), mahi mahi, and more. Our tourists spend delightfully on fishing trips for our world record breaking marlins and sailfish. Local sustenance and recreational fishermen enjoy the bait fish as meals.
There is no doubt that there is an irreplaceable demand and need for the fish stock that Mandahl provides. The challenge is to maintain a sustainable status quo that benefits all uses while maintaining healthy marine populations. The only way this can be achieved is with regular fish counts, take limits, and appropriate temporary species closures based upon the Mandahl Eco-system.
(Currently, stock assessments are made for the entire US Caribbean region … which includes Puerto Rico, albeit work is now being done to assess specific islands individually. However, from my diving and exploring hundreds of land and water locations around St. Thomas and St. John, I believe we need to look at area-specific ‘spot-closures’ around each island that would allow the fishing industry to continue to harvest mobile species year-round, while letting Eco-systems they’ve departed recover. That’s a thesis-length article I will be presenting at the end of this season).
So, we placed our cameras to film the water regions where bait fish would normally run in large numbers at this time of year. What we found was a general scarcity (though not lack of) silvery bait fish species. In particular, we sought out Redear Sardine and various other anchovies, herrings and scad.
Silvery bait fish were not the predominant fish detected by our cameras. What we caught were silvery species of mullet, jenny, mojarra and young snapper.
Small schools of fry (it is near impossible to tell individual species without capture) dotted the shallows, but also nowhere near historic numbers. These fry were enough to attract small herons and egrets, in particular Little Blue Herons and Green Herons. That the birds were hungry was evident in that they were allowing much closer human (fishers and beach-goers) encroachment than typical.
___________
Tomorrow, in Part 3, we will look at February’s signs of recovery, and retreat from recovery, at Mandahl.
___________
Patrons: Download full resolution, non-watermarked images from today’s article through this link.
Not yet a patron? Follow this link to sign up to ‘Be A Part of Something Green©’ today. Your generosity assists youth Eco-education, research and conservation activities of the Camp Umoja Non-profit Eco-learning Center located at Mandahl Bay, St. Thomas, Virgin Islands. IN return, we have lots of nifty things for you. See the various tier levels for associated benefits!
ENJOY YOUR DAY. 🙂
~ Karl
