Why daisy chains?
Some guys have a knack for finding fish offshore. It seems like a lucky few stumble into foamers all day, but I'm definitely not one of those guys so I spend a lot of time trolling. Trolling doesn't just find you fish, it finds you biting fish. It allows you to cover lots of water, attracts fish to your boat without having to chum and can be used to determine if a school of fish is willing to bite. I used to think that trolling was simple: you dump a few lures behind the boat and drive until you get bit. In recent years, I've learned that trolling is really an art and there are ways to be good at it. The ideal position of the jigs behind the boat and the optimal speed vary widely based on the boat and conditions, but the sizes and colors of the trolling jigs and the tackle used also play a notable role. In my opinion, the most effective trolling rig for tuna is the daisy chain.
Daisy chains are simply a string of lures that mimic a small school of baitfish, with the final lure in the chain having a hook. Over the years, I've learned that there are good daisy chains and there are AMAZING daisy chains.
Lure Selection
Most daisy chains consist of a few small lures followed by a larger lure with a hook. I recall a specific day when I was trolling such a daisy chain on an outrigger and I got short bit a dozen times and couldn't figure out why the fish weren't sticking. I decided to carefully watch the daisy chain as we were trolling and I watched multiple fish attempt to eat the smaller teasers at the beginning of the chain and completely ignore the larger lure at the end. Since the concept of a daisy chain is to mimic a school of baitfish, each lure in the daisy chain needs to be the same size and color.
Color
There are so many colors of trolling feathers floating around the internet, but really only a few that we use in Southern California. When you're listening to the radio in summer, there are only 4 color combinations that are consistently called out: Black/Purple, Green/Yellow (aka zucchini), Green/Yellow/Red (aka Mexican flag), pink.
Black/Purple: Bass and tuna fisherman usually go by the motto, "dark skies, dark lures." I used to only run black/purple jigs at dawn and dusk, or if the skies were overcast, but I've learned that black/purple will get bit at all times of day. Bonito and skipjack seem to prefer darker lures so I always run black/purple when they are around.
Pink: Years ago, when albacore roamed our waters, I recall a tuna trip where we struggled to keep a school of tuna with the boat, so we ended up trolling all day, picking up 1 or 2 fish at a time. Pelagic red crabs were everywhere and the vast majority of our bites came from a bright pink feather. I assumed that a tuna looking at a feather on the surface against a bright sky wouldn't be able to tell what color a feather was, and I certainly wouldn't have picked a solid pink feather to consistently stop the boat, but I couldn't argue with results. Since then, I always run a bright pink lure when there are red crabs around and it never fails to produce. Oddly, red feathers, which more closely resemble the color of pelagic red crabs, have not worked well for me.
Zucchini and Mexican Flag: I'm grouping these together because they are so similar, the only distinguishing feature being a red stripe on Mexican flag. However, some people have a strong preference for one or the other. I previously believed that these two colors were equally effective, but this past fall I was trolling off Sunset Cliffs looking for bonito and was struggling to get bit on a Mexican flag feather despite seeing bait, boils and crashing birds. I got on the radio to ask what the bonito were biting and was told that they were specifically keyed in on zucchini jigs. I switched from Mexican flag to zucchini and immediately started catching fish. I had never heard of a small red stripe on a lure making such a difference, especially for hungry bonito, but that day it did. I used to be satisfied running a Mexican flag OR zucchini feather, but now I treat them as distinct colors and drag Mexican flag AND zucchini feathers when trolling.
Rigging
Swivels: All trolling feathers are run behind a swivel because every trolling lure spins and the swivel also reduces line twist when a tuna is spiraling under the boat. Typical crane swivels reduce line twist in a severely twisted line, but a high-quality ball-bearing swivel eliminates virtually all twist from a line.
Hooks: Almost every daisy chain that I've seen online or in big-box stores has a large inline single hook crimped directly to the line. This is a great setup for billfish, but not so much for tuna. When a fish bites an inline hook, it needs to turn its head in order for the hook to stick in the corner of its mouth. When trolling, the hook is frequently pulled from a fish's mouth before it can turn its head, resulting in short strikes. Double hooks dig into a fish as soon as they bite, which significantly increases the hookup rate when trolling. Threading the double hook through a swivel reduces line twist, prevents the hook from chafing the line and makes it easy to swap hooks if they become dull or a different size is desired.
Connections: I've bought a few rigged trolling lures that had crimps that failed under a few pounds of tension. I don't trust crimps on purchased lures because it's very difficult to tell if a crimp has been done correctly. However, you can do a quick visual inspection to tell if a knot has been tied correctly or not. Crimps are necessary when the line is connected directly to the hook to prevent chafing, but when hook is threaded onto a swivel that is connected to the line, the hook does not chafe the line when a fish is shaking its head during a fight.
Here a link to purchase a perfectly rigged daisy chain.