I’m happy to hear that your Mustang stallion is doing so well.
Male seahorses are typically somewhat less active than the females. The stallions tend to be real homebodies that will often choose one particular hitching post as their home base and spend much of there time perched right there (think of your Dad hunkered down in his favorite easy chair in the den). Researchers studying seahorses in the field therefore refer to males as "site-specific" because they can be found at the same tiny patch of reef or seagrass day after day, rarely straying from their chosen spot. Whereas females seahorses roam over a home territory of up to one hundred square meters, the male will spend most all of this time hanging out at his tiny base of operations within his mate’s much larger territory.
As a result, mature males are often naturally more shy and retiring than females, which can be quite brazen at times. I suspect this is due to their parental duties — during the breeding season, pair-bonded males are ordinarily ALWAYS pregnant, and they can’t risk exposing their precious cargo to any more risk than absolutely necessary.) So normally the unfettered females tend to be far more footloose and fancy free, a little more on the frisky side, while the males are often more shy and retiring.
It’s a bit out of the ordinary for your female to be timid and reclusive, but all seahorses have distinctive personalities, for sure, and she may simply be a little more meek in nature than most fillies. Your tank has a thriving pod population, so no doubt she’s been grazing on the natural fodder in your aquarium. That may be why she is spending a lot of time hanging out in the background behind the rockwork — that may be where the hunting is best in your reef since amphipods and copepods like to hide out in the darker nooks and crannies amidst the live rock and coral, right along the substratum.
But we want to encourage your filly to come out in the open, where you can observe her and enjoy her presence, and it’s important that she learns to eat from your feeding station, so I would concentrate on that for now. I would try target feeding her at least once or twice a day, as described below, so that she learns to associate your presence with good food and a full belly. Seahorses are ruled by their stomachs, so once she learns to recognize you as the giver of gourmet delights — the source of her favorite goodies — and is readily accepting frozen Mysis from your baster or feeding wand, it should be an easy matter to lead her out from the background into the open and teach her to eat from your feeder. Before you know it, she’ll be heading for your feeding station as soon a she notices you approaching the aquarium.
The individual personalities of seahorses naturally extend to their feeding habits. Some are aggressive feeders that will boldly snatch food from your fingers, while some and shy and secretive, feeding only when they think they’re not being observed. Some like to slurp up Mysis while it’s swirling through the water column, and some will only take Mysis off the bottom of the tank. Some are voracious pigs that greedily scarf up everything in sight, and some are slow, deliberate feeders that painstakingly examine every morsel of Mysis before they accept or reject it. Some eat like horses and some eat like birds. So how does the seahorse keeper make sure all his charges are getting enough to eat at mealtime? How does the hobbyist keep the aggressive eaters from scarfing up all the mouth-watering Mysis before the slower feeders get their fair share? And how can you keep active fishes and inverts with seahorses without the faster fishes gobbling up all the goodies before the slowpoke seahorses can grab a mouthful?
Target feeding is the answer. Target feeding just means offering a single piece of Mysis to one particular seahorse, and then watching to see whether or not the ‘horse you targeted actually eats the shrimp. Feeding each of your seahorses in turn that way makes it easy to keep track of exactly how much each of your specimens is eating.
There are many different ways to target feed seahorses. Most methods involve using a long utensil of some sort to wave the Mysis temptingly in front of the chosen seahorse; once you’re sure this has attracted his interest, the Mysis is released so it drifts down enticingly right before the seahorse’s snout. Most of the time, the seahorse will snatch it up as it drifts by or snap it up as soon as it hits the bottom.
A great number of utensils work well for target feeding. I’ve seen hobbyists use everything from chopsticks to extra long tweezers and hemostats or forceps to homemade pipettes fashioned from a length of rigid plastic tubing. As for myself, I prefer handfeeding when I target feed a particular seahorse.
But no doubt the all-time favorite implement for target feeding seahorses is the old-fashioned turkey baster. The old-fashioned ones with the glass barrels work best because the seahorses can see the Mysis inside the baster all the way as it moves down the barrel and out the tip. By exerting just the right amount of pressure on the bulb, great precision is possible when target feeding with a turkey baster. By squeezing and releasing the bulb ever so slightly, a skillful target feeder can keep a piece of Mysis dancing at the very tip of the baster indefinitely, and hold the tempting morsel right in front of the seahorse’s mouth as long as necessary. Or if the seahorse rejects the Mysis the first time it drifts by, a baster makes it easy to deftly suck up the shrimp from the bottom so it can be offered to the target again. In the same way, the baster makes it a simple matter to clean any remaining leftovers after a feeding session. (You’ll quickly discover the feeding tube is also indispensable for tapping away pesky fish and invertebrates that threaten to steal the tempting tidbit before an indecisive seahorse can snatch it up. And it’s great for tapping on the cover to ringing the dinner bell and summon the diners for their gourmet feast!)
In short, target feeding allows the hobbyist to assure that each of his seahorses gets enough to eat without overfeeding or underfeeding the tank. And it makes it possible to keep seahorses in a community tank with more active fishes that would ordinarily out-compete them for food, since the aquarist can personally deliver each mouthful to the seahorses while keeping more aggressive specimens at bay.
The key to keeping active specimens like firefish or cleaner shrimp successfully with seahorses is to feed the other fish and inverts with standard, off-the-shelf aquarium foods first, and once they’ve had their fill, then target feed the seahorses.
In the meantime, Harry, if you want to make sure your female is getting enough to eat, try to get a good look at her cross-section to see if she is losing weight. Compare her girth to that of your Mustang stallion who you would know is eating well. Here’s what to look for:
Basically, you just want to make sure all your seahorses have full bellies at the end of the day, as indicated by their well-rounded abdomens. After a good feeding, the seahorse’s belly rings should be flush or even slightly convex in cross section when viewed from head on. (We never want to see sunken, severely pinched-in abdomens on our seahorses! Concave belly rings are a sure sign of an underfed seahorse, with the sole exception of a female that has just transferred her eggs.)
So if you want to check whether your female is eating well or not, Harry, don’t look at her profile — examine her head-on. Her abdomen or belly plates should bulge out slightly or at least be flush with their flanks, not pinched in or sunken. In other words, when viewed from the back or from head-on, the cross-section of her abdomen should appear concave "( )" or flush "l l" rather than concave ") (" or pinched in.
Best of luck with your new Mustangs, Harry! Here’s hoping you soon have your female eating right from your fingers.