The Search for the Nautilus Egg
Day 10/11: Husbandry Time!After a great day at sea, complete with a rainbow over one of our boats in the distance and lots more nautiluses in the trap, it's time to do some lab work! And with everything going on at sea, in the lab, in meetings, one of our main focuses is simply siphoning and scooping nautilus waste (poop and regurgitated chicken). Like all cephalopods, nautiluses are sensitive to water quality -- all cephalopds have what is called a microvillus epidermis, which means their skin is made up of tiny pores open to the water around them. Great for "good" things in the water but not so great for "bad" things in the water. We aim to keep all of the normal water quality parameters (ammonia, nitrite, nitrate) at zero, especially the ammonia, which is our focus. With all of our movement around the tank and inside the tank, the nautiluses don't seem to pay any attention. They are happy just hanging on to each other and resting a bit. Today is Sunday here in Fiji so no boat trips, but we have some other work to do to prepare for next week!
Day 10/11: Releasing NautilusesMost of the nautiluses we have been catching have been released right back to the wild (a small subset is being collected for research and education). When releasing nautiluses, it is critical to "burp" them and make sure that there are no trapped air bubbles in their mantle cavity. The air bubbles may get there when being measured and weighed out of the water. If the bubbles are not removed, the nautiluses are positively buoyant and will not be able to jet back down to their homes. To do this, we gently roll them around underwater so that their tentacles are facing up. This allows any bubbles to escape out of the hyponome (term for the funnel in nautiluses). Once they are neutrally buoyant and no other air bubbles come out, a quick free dive down a ways, then off they go. We know this method works because we have recaptured ones we've caught in other areas and we have also placed transmitters on others that we follow around on other trips. While I grew up wanting to be a researcher, I never thought that my "science" would involve burping an animal! Haha.
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