Iburi Communications Vol. 118 "Manta Ray!!... No, it's not."

Just when you think one has passed, another typhoon appears. Every time we check the weather forecast, we at Iburi Center are constantly on edge. And at Iburi Center, there are creatures that become especially restless when it's feeding time. The star of this story, who leisurely swam past us, is called the "Dwarf Spinetail devilray." The Dwarf Spinetail devilray grows to a maximum of about 2 meters, and is a different species from the "Spinetail devilray," which can grow to over 3 meters. Currently, there are two Dwarf Spinetail devilray living at Iburi Center. When customers see them, we often hear them say... "It's a manta ray!!"... Close!! Manta rays are generally said to be a collective term for three species belonging to the family Spinetail devilray yarae (giant manta ray, Alfred manta, and Atlantic manta ray). The Dwarf Spinetail devilray is also a member of the same Spinetail devilray yarae, but strictly speaking, it is not a manta ray. There are significant differences between the so-called manta rays and the "Dwarf Spinetail devilray" at the Iburi Center, one of which is the location of their mouths. ▼ Alfred manta ▼Dwarf Spinetail devilray Alfred manta at the Kaiyukan Spinetail devilray have their mouths located towards the front of their bodies, while the Dwarf Manta Rays have theirs on the underside. Although smaller than their relatives, the Dwarf Manta Spinetail devilray are no slouch when it comes to swimming. They flap their large pectoral fins to the sides and swim gracefully through the water. However... when it's feeding time, that graceful demeanor completely changes. They accelerate from a distance and dash towards the ladle filled with food, eating it as if they're sprinting. Even the aquarium keeper who see them every day can't help but exclaim, "That's fast!" Normally, the Dwarf Spinetail devilray swims gracefully using its large pectoral fins, but at feeding time, it transforms into a dynamic spectacle. Not only their appearance, but also this contrast in behavior is one of their charms. These sometimes graceful, sometimes fierce manta Spinetail devilray can currently be seen at only two facilities in Japan, one of which is the Iburi Center. While not usually open to the public, it is open to the public to the extent that it does not interfere with research, in order to support regional development. For more information, please contact the Tosashimizu City Tourism Association. If your timing is right, please come and see them! We await you in far-off Tosashimizu!

Marine Biological Research Institute "Iburi Center"

2026.10.07

Happy Birthday Miu!!

Hello everyone!! Two months ago, on August 17th, it was the 8th birthday of Asian small clawed otter, Miu!! Currently, Miu lives in the back area with Popo. For her birthday, we gave her a "Birthday Ice Plate" as a present. The plate was decorated with colorful ice filled with slices of rainbow trout, smelt, and wakasagi to form the number "8" for her age, and was decorated with a heart made of red jelly and flowers made of salmon. We wondered if she would like it...? When we entered the room and showed her the plate, she let out a loud cry, as if to say, "Give it to me quickly!!!" (lol) We took a video of us giving her the plate, so please take a look! The moment we handed it to her, Miu and Popo immediately approached the plate and started eating with great speed (lol). It was so heartwarming to watch them skillfully grab the ice with their paws and melt it in the pool water as they ate, and we couldn't take our eyes off them!!! The two of them happily finished it all together! Once again, happy birthday, Miu!! All of us aquarium keeper hope that you will continue to live a happy and healthy life!!

mammalian

2026.10.05

Iburi Newsletter Vol. 117: "I tried taking a picture of a planula!"

This is Iburi Center. Well, the jellyfish season has arrived again this year. /There's a massive outbreak of those jellyfish! \That's right! A symbol of summer! Octopus jellyfish!!!! Their polka-dot pattern gives them a cool and refreshing look (at least in my opinion), making them perfect for cooling off. Check this out too. → Speaking of summer, octopus jellyfish! This time, we collected smaller individuals and are aiming to raise them slowly to be on long-term display. We've been diligently visiting the octopus jellyfish breeding grounds, waiting for the perfect moment for them to appear, and we've managed to collect some nice, newly emerged small individuals and send them to the Kaiyukan! Now, since Iburi Center is a research facility, it would be a bit of a waste to just collect them! So, we decided to try collecting planulae. Planulae are the stage before polyps, which are part of the jellyfish's life cycle, and securing them is absolutely essential for breeding jellyfish that release planulae! These tiny, grain-like things scurrying around as if to say "Excuse me, I'm coming through" are planulae. This time, we tried various methods, such as releasing multiple jellyfish into a bucket and directly collecting them with a dropper. After about a week...? They've become proper polyps! Yay! Lol So, we sent these to the Kaiyukan as well. If the jellyfish hatch successfully, we might be able to see captive-bred spotted jellyfish at the Kaiyukan! I can't wait!!!

Marine Biological Research Institute "Iburi Center"

2026.10.03

Tiny baby pufferfish have been born!

Hello everyone! Today we'd like to introduce some baby pufferfish that were born this spring. This is an adult Porcupinefish (English name: Porcupinefish) living in the Cook Strait tank . It's related to the Long-spine porcupine fish, but unlike the Long-spine porcupine fish, whose spines only rise when it inflates, the black-spotted porcupinefish's spines are always raised. Next is a baby Porcupinefish. Your honest reaction is probably, "What is this??" (laughs) Actually, each of these tiny bumps is a baby! On May 3rd of this year, while diving to clean the Cook Strait tank, we discovered eggs laid on a rock. We immediately moved them to the back area and began raising them. Since then, we've been carefully raising them by changing the water, feeding them, and cleaning the tank every day, and they've grown this big! As of September 18th, they are about 5cm in size. When people approach, they flap their tiny fins as if to say, "It's feeding time!" They're so adorable, aren't they? Currently, these baby Porcupinefish are on display for a limited time from September 5th at the aquarium keeper counter in front of the "Swirling Coral Exhibition" on the 4th floor of the entrance building! Please come and see their adorable appearance, which can only be seen at this time! *Please note that the exhibition may be suddenly canceled depending on the condition of the animals.

Fish

2026.10.01

My favorite fish, part 2

The other day, a young staff member introduced the yellow coral goby in "My Favorite Fish." This time, I'll introduce my "Favorite Fish" from freshwater fish. Japanese freshwater fish tend to have duller colors compared to saltwater fish that live in coral seas and the like. Perhaps it's because they live in rivers, ponds, and swamps, so their colors are suited to those environments. Nevertheless, their breeding colors during the breeding season and the red accents on young Red spotted masu salmon are truly eye-catching. ▼ Freshwater minnow(center), Dark chub(upper right)▼ The patterns on Red spotted masu salmon are also very interesting, such as the Oyanirami, which looks like it has a small fish on its side, but my favorite is the striped loach. ▼Oyanirami▼Striped loach It's a type of loach, so it has whiskers, but the loach eaten in Yanagawa hot pot has 10, while the striped loach has 6. The striped loach has been classified into several species: the large striped loach, the western striped loach, the eastern striped loach, and the Tosa striped loach, but I'm not sure which one my loach is. It won't stay still, so I can't get a good look at it, and classification seems impossible without examining its DNA. In the "Japan Forest, they're in the section with the Freshwater minnow and the waterfowl section, but you're more likely to see them in the waterfowl section. My favorite feature is the pattern on its side. There are rounded black spots lined up like dumplings in the middle, and the pattern above them looks like the movement of an electrocardiogram (lol). It's incredibly cute watching it wriggle around on the bottom, occasionally plunging its face into the gravel to munch on its food! In nature, they eat animals such as earthworms and water fleas, as well as algae, but I think they probably repeat this process of wriggling → plunging → chewing. Just as I was struggling to take a picture, two of them seemed to be searching for food. It's unusual as they're usually alone. One of them had something in its mouth and was shaking its head, so I wonder if it found something good? Try to find my favorite, too!

Fish

2026.09.28

A new breeding challenge

Previously, we informed you about the renovation of a spare room used for breeding fish. → Renovation of a certain room We are currently trying to breed two or three types of fish in that room. This time, I would like to talk about the breeding status of one of those types. The type we are trying to breed is the " Golden snapper " which is on display in the "Cook Strait" tank . It is a fish that lives around Australia and New Zealand and resembles the Splendid alfonsino. If you look at the top of the tank first thing in the morning, you can see behavior that looks like spawning. Once spawning is confirmed, you can collect the eggs by placing a net over the skimmer (the outlet that leads to the filter tank) installed on the water surface. Raising the fry from these eggs is very difficult, and they all die within one or two weeks due to various reasons such as food, water quality, and light. Newly hatched fry have underdeveloped eyes and mouths, and if they cannot eat when their mouths and intestines have formed, they may starve to death, so daily observation is very important. With each subsequent breeding cycle, we made improvements, trying things like changing the color of the tank, using new feeds, and improving water quality by continuously flowing seawater (this latest renovation made it possible to continuously flow seawater in each tank). As a result, we have been successful in raising fish for about a month. Here is a video of the fry about a month after the start of breeding. ↓ Currently, all the fish die again around the one-month mark, so we are investigating the cause. The future of breeding is unknown, so we will continue to raise them by trial and error, hoping that one day we will be able to display them in front of customers.

Fish

2026.09.26

Respect for the Aged Day (Otter)

The lifespan of an Asian small clawed otter is 14 to 15 years, but some can live for over 20 years. The oldest otter in Japan is Nikki at our facility. Her record of 23 years and 2 months is thought to be among the best in the world. ▼Nikki (I think it was her 20th birthday) The oldest otters currently living at our facility are the three siblings Nira, Zakuro, and Shuro. As we celebrated their birthdays recently, they have all turned 17. They were born as four siblings, and unfortunately Iga passed away early, but it's surprising that all three have lived this long. In fact, Hachi at NIFREL is older than the three siblings, turning 18 this year. Hachi, how are you? All the otters listed here are males, so it's a gathering of old men. Males tend to live longer at our facility. This is partly because the vast majority of otters born here are males... ▼Nira▼Shuro▼Zakuro The next oldest is Gumi (female), who will turn 14 in December. Recently, I underwent surgery to remove a mammary gland tumor and am now recovering! It was painful, but I did my best. So, let me introduce you to Nira and the others when they were little! These are the three cubs just a few days old. I think these are the three cubs other than Shuro. These four were on display at the special exhibition "Fureai LIVE-kan" that was being held at the time. Here are some photos from that time. I think they were about three months old. From left to right, I think these are Shuro, Nira, Zakuro, and Iga (not sure). After the special exhibition ended, they spent a long time in "Japan Forest". Here are some photos from that time. Is Zakuro the one looking this way? Compared to this time (I think they are 6-7 years old), their size has decreased slightly and their fur is in worse condition, but these three have almost no kidney stones, which are common in Asian small clawed otter. Each of them has a few minor ailments, but they are healthy. The temperature and water Japan Forest will drop from now on, and the footing will be hard on the older individuals, so they will all be living in the back area for a while. Zakuro, in particular, will be living alone because she tends to fight with the other two. You've never really tried to get along with your siblings, have you...? It seems your personality hasn't changed even as you've gotten older (laughs).

mammalian

2026.09.24

The secret of the South American coati

Let us introduce you to the energetic South American coati living in the "Gulf of Panama" tank ! - Hanging from the ceiling - Zero gravity!? - Three coatis sleeping in a tree As you can see in the pictures, South American coati are adept at climbing trees and moving along wire mesh. Why is that? The secret lies in their feet. ↓Front legs↓Hind legs If you look at the soles of their feet, you'll see that both their front and hind legs have toes that are far apart and spread out in a fan shape, allowing them to firmly grasp things. Their claws are also long and sharp, which they can use to stabilize themselves by hooking onto tree bark and other surfaces. In the wild, they live on the ground as well, but they sleep and breed in trees. Also, since they like to eat bird eggs and nuts, being able to move around in trees is very important for the survival of South American coati. In this tank, you can often see them moving around using their physical characteristics to their advantage, even during the day. When you visit, be sure to pay attention to the trees and the wire mesh on the ceiling!

mammalian

2026.09.21

Happy birthday, Shii and Buna!

Hello everyone! On August 23rd, it was the 3rd birthday of our otters, Shii and Buna, who were born at our facility! (The other two have already moved to other zoos/aquariums.) Time flies! On that day, we presented them with a handmade plate and a decorative ball! As for their reactions... Shii was scared of the decorative ball and didn't get too close, while Buna was very interested in the decorative ball feeder (lol). Afterwards, they apparently reached for the ice on the plate (lol). We were so happy to get such a great reaction from them! Thank you, Shii and Buna, for always bringing us joy! We hope you continue to live healthy lives!

mammalian

2026.09.16

The Tufted puffin journey to its new home, Part 3: Departure imminent.

The day of departure for the Tufted puffin is finally approaching. This tufted puffin blog will also be coming to an end soon... As the final day draws near, the aquarium keeper in charge are feeling increasingly sad. In this blog post, we will introduce the Tufted puffin puffins' food. First of all, the Tufted puffin at Kaiyukan usually eat sand eels, capelin, and krill. So the aquarium keeper have prepared a special meal for the Tufted puffin puffins with a message in mind! This is made mainly with sand eels, which everyone loves, and cut capelin! Oh? It seems like everyone except the rockfish is recoiling in disgust... I can feel a great distance between them... (laughs) I thought I had chosen some nicely curved sand eels, but it turned out to be a rather weak cheer. (laughs) However, as soon as the aquarium keeper left, they all went to eat, and when I checked back later, about half of it was gone! That's good. That's good. I will miss them, but eat plenty and stay healthy in your new home!

birds

2026.09.15

Record of the Tufted puffin's Move - Part 2: Everyone's Birthdays

Hello! This time, we'll show you how the Tufted puffin celebrated their birthdays. The Tufted puffin ' breeding season is from spring to summer. That's why many of the Tufted puffin living at the Kaiyukan Kaiyukan are born in July or August. This year, everyone was able to celebrate their birthdays in good health! And this year is a memorable 1st birthday for Iwabokke! Iwabokke still has a very innocent look on his face, but he has safely reached his first birthday. So, how old are they all this year? Okoppe: 15 years old Kerochi: 16 years old Tokoro: 16 years old Shari: 12 years old Saruru: 7 years old Chirippu: 5 years old Iwabokke: 1 year old When you line them up like this, you can see that we have Tufted puffin of a wide range of ages living together, from 16 years old to 1 year old. Spending time together every day, you can see that each one has their own personality and behavior, and there are changes that can be seen as they get older. This time, we'll show you photos of the Tufted puffin' birthdays. Please pay attention to each of their expressions. By the way, we tried celebrating the July birthdays with "ice"! However... everyone got quite scared and ended up acting in a way that wasn't very birthday-like. ▼Shari▼Chirippu (born at Kaiyukan) And last to celebrate its birthday was "Iwabokke"! After seeing the July group's reaction, the aquarium keeper changed their strategy a little. We gave Iwabokke the first "smelt" and "krill" it had ever eaten! So, what kind of reaction did Iwabokke show? Be sure to check out the video to see what happened. Iwabokke didn't touch the krill... and only ate the smelt (lol) The record of their move continues! Stay tuned for the next episode!

birds

2026.09.02

My precious, precious Artemia

It's already the latter half of August, but the hot days continue. The new school term is just around the corner, so please take care not to get sick. We aquarium keeper are also working hard while drinking our special juice to beat the heat. Gulp, gulp...ahh! Delicious!!! Even if you're drenched in sweat and exhausted, drinking this will give you 100 times more energy! You can work for hours! ...Sorry, I'm just kidding. This orange, seemingly delicious (?) liquid is the star of today's show, "Artemia". If you dilute the orange liquid a little and take a closer look, you can see that it contains many tiny granules. Each of these is an Artemia. They are crustaceans, like shrimp and crabs, and this is the "nauplius larva" stage when they are newly hatched. Because these Artemia are so small, they are very important creatures in aquariums as food for plankton-eating creatures such as jellyfish and newly hatched fry. If you see Spotted garden eel stretching their bodies out and opening and closing their mouths, or if the clover-like patterns on the Moon jelly are tinged orange, it means they're right in the middle of feeding time. If you look closely inside the tank, you might even spot tiny Artemia floating around!

Fish

2026.09.01