# @stem_antics on Instagram

- **Type:** Video
- **Original URL:** https://www.instagram.com/p/Ddy5g5DAM7Z
- **Gondola URL:** https://gondola.cc/posts/71131442-stem-antics-instagram
- **Thumbnail:** https://img.gondola.cc/tr:w-,h-,fo-auto/postThumbnails/19e2c5bd64.jpg
- **Posted:** 2026-09-27T15:10:38.000+00:00
- **Account Owner:** Stem Antics (@stem_antics) — https://gondola.cc/stem_antics

## Caption

Bluefin tuna are among the most metabolically extreme fish on Earth, and farming them has forced aquaculture engineers to rethink something as basic as how to deliver a meal.

Most bluefin “farming” is actually ranching. Wild juveniles are captured, towed in net pens to coastal sites, and fattened for months before harvest. Australia pioneered this with southern bluefin at Port Lincoln in the early 1990s, and the Mediterranean and Japan followed at scale.

Why fire the food through the air?

- Bluefin are regionally endothermic. A counter-current heat exchanger, the rete mirabile, holds their swimming muscle well above water temperature, which demands an enormous and continuous caloric intake
- They are obligate ram ventilators and must keep swimming to push water over their gills, so they circle the pen at speed rather than waiting at a feeding point
- Pens can exceed 50 metres in diameter. Dropping baitfish over one spot lets dominant fish monopolise the meal while smaller fish go hungry
- Pneumatic feed cannons launch sardines, mackerel and squid across the whole surface in seconds, spreading the ration so the entire school can feed at once
- Rapid, wide distribution means more feed is eaten before it sinks through the net, which cuts waste and limits nutrient loading on the seabed below

The trade-off is brutal efficiency. Ranched bluefin commonly need somewhere in the region of 15 to 20 kilograms of wet baitfish to add a single kilogram of body mass, so every design choice in the feeding system targets consumption rate and waste reduction.

The long-term goal is breaking dependence on wild stock entirely. In 2002, researchers at Kindai University in Japan, led by Hidemi Kumai, closed the full Pacific bluefin life cycle in captivity after more than three decades of work.

Feeding a living torpedo requires a delivery system built for its speed.

#stemantics #aquaculture #marinebiology #bluefintuna #foodengineering

## Stats

- **Views:** 50,563
- **Likes:** 445
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- **Comments:** 2

## Tags

bluefintuna, aquaculture, marinebiology, stemantics, foodengineering

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