Sunshine Aquarium Living Discovery Communication vol.27 - May 20th is "World Metrology Day": Animal Weight Measurement and the Dedicated Care by Staff

On Wednesday, May 20th, weight measurements for animals such as otters are scheduled to take place!

Sunshine Aquarium (Ikebukuro, Tokyo), which marks its 15th anniversary this year since its full renovation in 2011, exhibits approximately 23,000 creatures across 550 species. Daily health management by zookeepers is essential for these animals to live vibrantly. Just as there are diverse species, the methods of health management vary.

In this edition of Discovery Communication, coinciding with "World Metrology Day" on May 20th, we introduce the health management initiatives of the animals living at Sunshine Aquarium. We will show how staff measure the weights and manage the conditions of various animals including otters, sea lions, penguins, and reptiles. Through the behind-the-scenes look at husbandry that is usually unseen, we deliver the steady efforts of staff who protect the health and lives of the creatures.

*What is World Metrology Day? It is a day commemorating the signing of the Metre Convention on May 20, 1875, aimed at the international unification of weights and measures.

Stepping on the scale is not a given: The meaning and behind-the-scenes of weight measurement

Weight measurement is a fundamental part of health management, indispensable for early detection and treatment of diseases. From daily numerical changes, staff can read signs of obesity or illness, helping to optimize nutritional management of food, calculate dosage for appropriate treatment, and collect basic data for proper growth promotion and breeding.

Weight measurement allows the understanding of health conditions with almost no burden on the animals. By incorporating it into daily routines, even slight increases or decreases in weight can serve as indicators of changes in physical condition in a captive environment. Thus, regular weight measurement and daily health management are more important than anything else.

However, weighing animals is not easy. They may be wary of the unfamiliar object called a scale and not approach it, move around so much that the reading won't stabilize, or other individuals might jump on the scale together. Various challenges arise, necessitating creative measures for measurement.

Therefore, we use special measurement tools and a method called "Husbandry Training" for weighing a wide variety of animals.

The importance of interaction between staff and animals! What is Husbandry Training?

Measurement methods vary by animal, and specialized tools or scales suited to the species and size are used. However, a scale is an unfamiliar object to animals. Placing it suddenly in their living space might cause them to avoid it out of caution. While staff could catch and place them on it, animals may resist being caught, or even if placed, they may struggle, making it difficult to get an accurate reading.

Therefore, it is necessary to first get the animals used to the "scale" and then draw out actions where they voluntarily step onto it. In "Husbandry Training," we aim to conduct health management such as weight measurement, palpation, and treatment safely for both parties while encouraging voluntary actions without stressing the animals.

In training, staff prepare an environment where it's easy for animals to perform the desired actions and keep saying "OK" when those actions occur. As desired actions increase, for example, the animal will come to stand on the scale. This makes it possible for both parties to weigh the animal safely, easily, and with low stress. The secret to success is to train gradually over a month to several months, depending on the species, individual, and environment.

Husbandry Training is useful not only for weight measurement but also for checking hard-to-see areas like the inside of the mouth or between toes, and for measuring body temperature. If procedures like blood collection and X-rays can also be performed, diagnosis can be made without anesthesia, making it an important training that reduces the physical and mental burden on the animals!

《Weight Measurement of Otters》

The weight of a small-clawed otter is about 3 to 4 kg. The appropriate weight varies by individual and fluctuates with age, activity level, and season. By measuring weight once a week, we adjust the amount of food and maintain an appropriate weight.

In the weight measurement of small-clawed otters, we gradually clear three points: (1) not being afraid of the scale, (2) stepping onto the scale, and (3) staying still on the scale.