How to Catch Mahi-Mahi

Part 1 of the Mahi-Mahi Florida Keys Fishing Instructional Series

So you want to learn how to catch mahi-mahi? In this blog post, we’ll look at the Atlantic Ocean currents that mahi-mahi use as migration highways to arrive in the Florida Keys.

The Atlantic Ocean Gyre

The North Atlantic Gyre is an extensive system of clockwise currents comprised of three main currents: 

  • The Gulf Stream: The largest and most well-known current in the gyre. It originates in the Gulf of Mexico and flows north along the east coast of the United States before crossing over to Europe. 
  • North Atlantic Drift: The North Atlantic Drift is a weaker current that flows from the Caribbean Sea towards Iceland.
  • Canary Current: The Canary Current is a cold current that flows south along the west coast of Africa.

Commercial Potential of Pelagic Sargassum spp. in Mexico – Scientific Figure on ResearchGate. Available from: https://www.researchgate.net/figure/Major-currents-in-the-North-Atlantic-the-Sargasso-Sea-and-the-Great-Atlantic_fig1_356170624 [accessed 3 May, 2022]

The Sargasso Sea

The Sargasso Sea is a giant Atlantic Ocean gyre located in the middle of the North Atlantic Ocean. This unique aquatic region is rich in nutrients, which support various plant and animal life.  Additionally, the Sargasso Sea provides an important breeding ground for migratory pelagic fish, mahi-mahi, yellowfin tuna, and wahoo, to name a few.

Mahi-Mahi Migration Pattern Map

Studies show that the mahi-mahi, like a bird, travels north for the summer and south for the winter; this was long thought, merely an idea based on speculation until mahi-mahi tagging data became readily available.

Then, the Dolphin Research Center (www.dolphintagging.com) started tracking mahi-mahi movements throughout the Atlantic Ocean using their innovative tagging systems; now, we can see what our oceans are telling us through this data.

Based on the tagging study results, I created this migratory mahi-mahi map to help beginners understand the migration patterns. 

How to Catch Mahi Mahi

These map show the migratory ocean current highway routes that mahi-mahi may use to travel to and from the Florida Keys; along with this travel map, you can see the migratory highways paths these fish take to arrive at specific locations first in the Florida Keys.

Florida Keys GPS Fishing Spots

 

The Great Atlantic Ocean Sargassum Belt 

The Gulf Stream is a powerful ocean current that flows from the Gulf of Mexico to the coast of Florida. Along the way, it picks up a massive amount of seaweed known as sargassum. This seaweed then gets caught in a current known as the Great Atlantic Sargassum Belt, which runs from Florida to Africa. This belt typically contains a massive amount of seaweed, but in recent years the amount of seaweed has increased dramatically. Some scientists believe that this is due to changes in ocean temperature and circulation patterns. As a result of the increased seaweed, we see a thick mat of rotting vegetation. The sargassum first started showing up in large quantities in 2011, and it has had a devastating effect on the ecology of the Florida Keys. 

This rotting seaweed does more than increase the amount of seaweed biomass in these regions:

  • It heats the ocean surface and interferes with natural processes like bait feeding on sargassum.
  • Block sunlight from reaching coral reefs resulting in coral bleaching. 
  • Interferes with and changes fish migration patterns.

Changes in Mahi-Mahi Migration Patterns

 In 2011 this increase in dead weed was directly correlated with a decrease in the number of migratory mahi-mahi observed in South Florida. Scientists believe that the massive biomass of dead sargassum may be interfering with the mahi-mahi’s ability to find food.

In addition, the vast amounts of sargassum have made it difficult for the fish to follow their natural migratory patterns along ocean currents, which has put them at risk of being caught in longline gear. As a result, this may be why we are seeing less mahi-mahi in the Florida Keys and other parts of the Gulf Stream ecosystem.

All animals, including birds and fish, will change migratory patterns based on environmental stresses. We need to understand these changes better to ensure that these fish populations remain healthy and sustainable.

Late Arrivals

In 2011, local charter boat captains and commercial anglers began to observe a distinct shift in the timing of mahi-mahi migrations. Whereas they had previously seen these fish arrive during late spring and early summer, they noticed that mahi-mahi were now appearing in more significant numbers later in the year, around August and September, after the tourism season ended.

It is a known fact there is a strong correlation between powerful hurricanes and tropical storms and large migrations of mahi-mahi into Gulf Stream waters. Thus, it seems clear that changes in Gulf Stream activity over the past decade have resulted in significant shifts in crucial fish migration patterns – something that all fishermen need to be aware of as they plan their fishing trips.

Conclusion

The patterns of the mahi-mahi migration are constantly changing due to environmental factors such as temperature and weather. Therefore, if you want to increase your chances of catching these fish, it’s essential to consider and plan your fishing trip accordingly. Stay up to date with summer mahi-mahi migrations by listening to our real time fishing reports through The Good Karma Sportfishing App. Learn more about our fishing reports by clicking here. Learning about the migrations patterns of mahi-mahi, you’ll be better prepared to go out on the water and have a successful fishing expedition.