Octopus (30 page)

Octopuses are different from most animals kept in captivity. Although they are mollusks, in many ways they are not like other mollusks. They live and compete with fish. They have evolved into a different niche—that of a fast-growing, short-lived marine predator. Amazing animals, octopuses do not easily fit into what we typically think of as a mollusk, so they are sometimes referred to as aliens of the sea. Understanding their life cycle and behavior in the wild can help one to make informed decisions about keeping one in captivity. Many people believe that keeping octopuses is extremely difficult, but with proper knowledge and marine aquarium experience, it is doable and fun.

Finding an Octopus

Obtaining an octopus is often a big challenge, especially if you live far from the ocean. There are several methods for getting an octopus for an aquarium. For most hobbyists interested in keeping a pet octopus, the easiest way to obtain an animal is to buy one at a local aquarium store. Even if they don't regularly stock cephalopods, some saltwater shops will special order an octopus. By going through a pet store, you can reduce the cost. If the octopus is already in the store, you can make sure the octopus is feeding.

To establish the health of an octopus, the easiest way is to observe whether it has a good appetite. Because pet stores buy through distributors and in bulk, a cephalopod at a local shop may cost about half what it would if you obtained it yourself through a mail-order company; the required overnight shipping is expensive and saltwater is heavy. And if the shipment has to cross a national border, it can become mired in red-tape permits and sometimes blocked by bureaucrats. When you purchase an animal through a pet store, you can examine it and ask the shop owners questions before you take it home.

When asking questions, keep in mind that pet shop owners often lack specific knowledge about octopuses and their care requirements. The online shops and mail-order houses usually know very little, too. For example,
many suppliers label all species of octopuses as the common octopus regardless of where they came from or the actual species. The animal you receive could be a baby with the potential to grow very large or it could be a full-grown adult of a small species that may have only weeks left in its lifespan. But most octopuses in the aquarium trade are in the small to medium size range as adults—rarely larger than a grapefruit.

Transporting an Octopus

Scientists and hobbyists alike are frustrated when transporting octopuses long distances is left to others. In addition to costing more than many marine fish and invertebrates, octopuses don't tolerate shipping stresses well, and there's always the chance of the animal inking during shipment, and the ink can kill an octopus. We've been told that almost any type of cargo has higher priority than live fish or invertebrates. Some octopus species are only available in certain seasons. And prices do not include shipping costs, which can be over fifty dollars for the smallest specimens and thousands of dollars for the largest.

If you live near the ocean and are comfortable in it, collecting an octopus from the wild is usually the best method. With some practice, you can select an octopus based on condition, size, and species. Be sure to check local fishing and other regulations before collecting any marine life, or you might receive a hefty fine. In Bermuda and the Caribbean, we often catch octopuses for research projects, mostly common octopuses (see plate 37), which can be found in shallow water while you are snorkeling. Snorkeling allows more maneuverability and more bottom time than diving. We use a diver's tropical fish-collecting net, which has an aluminum frame with heavy clear plastic on the sides and a screen bottom. These nets are designed to minimize stress on marine life: the plastic sides don't abrade an octopus's delicate skin like a coarse mesh net would. And these nets allow a collector to briefly transport the octopus out of the ocean while keeping it submerged in water in the plastic part of the net.

The trick to using these nets is to resist the urge to chase the octopus with them. While chasing after butterflies with butterfly nets works on land, divers and snorkelers are too slow and bulky to catch mobile marine life in their natural environment. Instead, place the net strategically on the bottom with the opening facing toward the animal you wish to catch,
one side resting on the bottom and another against a large rock. Hold the net as still as you can with one hand. Then, with your other hand, coax the animal toward the net. Sometimes you have to use a tickle stick or your hand to get the octopus to swim or crawl into the net. Any long, thin stick up to 3 ft. (1 m) can be gently used as a tickle stick. In Florida, yellow tickle sticks are commonly sold in dive stores during lobster season. You can carry a net in one hand and the tickle stick in the other. Use the stick to reach into places such as an octopus den, where you might not want to place your fingers, to help persuade its resident to leave. A tickle stick can also be used to extend your reach when trying to get an octopus to turn around when it is going away from the net.

Some collectors use chemicals to assist in catching octopuses (Roland is very wary of this practice because of the risk of damage to the octopus). Chemicals are used to persuade an octopus securely hunkered down in its den to come out. You can use a large syringe without a needle or a turkey baster filled with a chemical that is annoying to octopuses but not dangerous. Bleach, ammonia, or alcohol is often used for this purpose. The chemical is squirted deep into the den, and the annoyed octopus usually quickly vacates.

Once you have collected an octopus, the next step is to transport it to its new home. With oxygen and a little luck, octopuses can survive up to twenty-four hours in transit if they don't ink, and longer with water changes. Anything over this is pushing it unless there are water changes and near constant attention. Cephalopods simply do not ship well.

Personally taking a round-trip airplane ride may sound like overkill for obtaining an octopus in good condition. But for research scientists wishing to obtain a number of animals from a thousand miles or more away and ship them across international borders, it is often the most economic and viable solution. By being there, you can ensure that the octopuses have the best care during shipping and that they proceed through bureaucratic snags with the most haste possible. John Forsythe, formerly of the National Research Center for Cephalopods (NRCC), flew to Japan, Australia, and other locations to collect, pack, and escort cephalopods or their eggs back to the NRCC. In his expert care during every step of the trip, the animals had a much greater chance of survival.

In the cold Pacific waters off of Washington state and under the direction of Roland, giant Pacific octopuses and red octopuses are collected by Seattle Aquarium scuba divers. Timing and choice of dive site are important, since octopuses, particularly giant Pacific octopuses, are not seen during every dive. Collecting red octopuses by diving is usually easy, because this small species is found frequently during the day inside discarded beer bottles. At night they are even easier to find since they are crawling about. During the dive, the animals can be placed in plastic zip bags and then transferred to a small ice chest filled with water and an ice packet. If the travel time is less than one hour, the animal can be left in the plastic bag with no ill effects. For longer trips, the animal can be released into the ice chest. Only one animal may be held in each container; they will fight if they are kept together.

Giant Pacific octopuses are collected opportunistically. The Seattle Aquarium has a large cadre of staff and volunteer divers who report octopus sightings to the collectors, who then return to the site if an animal is needed by the aquarium. The dens are usually evident from their middens, although these octopuses are also frequently found out of their dens. While they are mostly nocturnal and more likely seen at night, divers prefer to catch these large octopuses during the day when they are more visible. Aquarium staff divers use a fish anesthetic, Quinaldine, to persuade the octopuses to leave their dens.

Once divers coerce the octopus out of its den, they wait to try to capture it until it is on sand or gravel or is swimming so it won't have anything solid to grab. Divers wrestle these octopuses into a large mesh diver's bag, usually with some difficulty, as the animals can be large and can cling to rocks with surprising strength. Once brought to the surface, the animal is
placed in a large ice chest or an even larger insulated tote for transport. The choice of transport container depends on the size of the animal; an animal up to 25 lb. (11 kg) can be transported in a 40-gallon (150-l) ice chest of chilled seawater. During trips longer than one hour, pure oxygen is bubbled into the chilled water. If transport time is shorter, the water is not oxygenated. Roland reports successfully catching and transporting octopuses up to 80 lb. (36 kg) using these methods. Upon arrival, the animal is transferred to a holding area, where it is weighed and measured. Everyone avoids handling the animals, especially with rough nets, because the octopus's skin is delicate and prone to injury from abrasion.