Years ago I have been pioneering Atlantic giant bluefin tuna freediving and was at the time, wondering if swordfish hunting could be done in the North Atlantic...
For the last three years I had unfortunaly to cancel several boat trips, mainly because of the unstable sea conditions far offshore ( just beyond the international waters ) in the North Atlantic: You must get a several days of sea becalmed period, if you plan to spot this fish from the boat. Observing the first dorsal fin and the tail of the fish exposed while it is swimming/ swaying like a shark on the sea surface gives you an exceptional exciting feeling.
It's well known that this billfish like to bask in warmer water, rapidly diving and hunting at regular interval in the day to the depth at about 1,000 feet: I guess this specific habit may give you the opportunity to hunt the fish.
This billfish capture made by a spearo is very rare, probably because of the fact that these deep pelagic do not school and are always seen by chance scattered, either singly.
Stories of sword attacking divers, whales , sharks and ... vessels is a traditional rumour in fishing circle: you can believe or not.
One of my colleague/ pro diver in Morocco has been a direct witness of a tragic attack made by an injured sword to a scuba diver in Spain: the guy shot with a pneumatic gun the fish trapped among bluefin tuna in a seine, the fish vanished in the depth with the spear. Then it suddenly rushed back a couple of min later to the same diver in piercing his thorax with the sword... it chose its agressor among a half dozen scuba divers working in the net! this fish is a clever hunter.
Mako shark and sfish are commonly found swimming at each other and sometimes fight... I was told by fishermen that sword hate swimming with dolphins: definitively a solitary pelagic
So we could recently heading on from Nova Scotia and boating 15h to an about ten miles square area lost in the middle of nowhere: swordfish is well known to be abundant there. About 200 miles in front off Cape Cod...
Full moon, sunny weather, 10 knots fresh wind...
A strong 1.5 knot current made the boat drifting far to the south every night.
A lot of masses of sargassum everywhere.
Whales, dolphins, birds... Action everyday!
I felt some anxiety about the abundance of sharks there such like great mako, GW: at the time we just arrived early morning, I could observe an amazing massive bull shark patrolling slowly on the surface and close to the boat. I was told by my friend that not any fisherman would try to swim there because they feel fear.
TOO LATE FOR THE SWORDFISH:
Why? mainly because the sea surface temperatur was too "hot" (at 63 F)
That makes this fish more distrustful and unpredictable, at the time you try to get close with the boat. An about 55 F is the best temp so that the fish stay longer and more calm on the surface.
We did scouting every day from sunrise to sunset (except a pretty rough sea day)
I did 4 attempts in 5 days by jumping from the boat as soon as the fish has been visually spotted on the surface and the boat close to the fish ( about 30 feet)
Action lasted a short time and I have to improvise, confronted with a technic dilemma:
-should I first dive straight, then back up to the fish (overweighted in his case as well as for the marlin hunting)?...
- should I first swim on the surface (light weighted) toward the fish, then follow the fish diving?...
I tried in vain the 2 technics : each time the water was clear ( but green ) and I unfortunately could not spot the fish before it took off in a split of second while vanishing to the depth. It seemed to feel fear, despite I did my best to dive calm and quiet.
A good point was that the fish seemed not to be afraid by the splash made by the diver, that's give you a chance to try a shot if the conditions are better.
In more fresh water things would probably be doing in a different way and much better ...so I will make an other attempt next year in spring/ cold water.
The team caught 9 swordfish by hand line (an amazing feat!) and harpooning from the boat: medium size from 250 to 400 lb. The max size there can be about 650lb. Swordfish is obviously a powerful fish with stamina and strength while fighting.
I opened each sword stomach and discovered mainly fresh squids, butterfish and deep/ strange fish probably taken pretty deep a couple of hours before the fish capture.
That could probably would confirm that the swordfish behavior surface in warmer water aids its digestion.
TOO EARLY FOR THE BIG EYE TUNA:
This was the second main goal of the expedition. This specie is for each spearo a pretty improbable encounter ...
A tuna school just arrived by chance at the end of our expedition on the area. It showed restless and scattered in clear green water
I did repetitive short dives but the school was as usually during the first days arrival swimming pretty fast strait away, much faster than any other tuna specie can do. Usually the school should gradually become "stabilized" in the area, but it takes a couple of weeks... diving approach should be more easy.
The team caught 6 pieces/ handline (trolling) : medium range 200 lb and one nice 230 lb. Exceptional captures.
A lot of albacore 20 lb to 40 lb were taken by trolling: they usually do swimming in front of the tuna pack. According to the captain experience, I cannot plan to spear there an over 60 lb albacore as I did 2 years ago in S.A.
Albacore and bigeye use to swim close to the surface ( less than 15 feet) during about 3h every day: from 2 to 5pm, 3 to 6pm the day after... bluefin tuna stay under the school in the depth at about 200 feet depth. The tide schedule plays an important part++
Fishermen use to chum with herrings there for bluefin tuna only (size: 200 to 500 lb max)
While systematically opening big eye tuna stomachs, I was surprised in finding fresh tiny octopus taken on the bottom by the fish at about 800 feet in the dark.
"Bigeye" predator!
As you know the best way to identify the big eye is by observing the liver which is striated and the both same size lobes.( in yellowfin the liver has a longer right lobe )
Thank,s again to my friend had he not had such a great experience, this report could not be shared!