Bonito (S/F)

“Bonito” is a name given to various species of medium-sized, predatory fish in the Scombridae family. First, bonito most commonly refers to species in the genus Sarda, including the Atlantic bonito (Sarda sarda) and the Pacific bonito (Sarda chiliensis lineolata); second, in Japanese cuisine, bonito refers to the skipjack tuna (Katsuwonus pelamis), which, in Japan, is called by its local name, katsuo; and, third, bonito can generally refer to any of various scombroid fish related to, but smaller than, tuna.

It can be assumed that the striped bonito (Sarda orientalis) was the species witnessed in 2001 by Dr. Alan Grant, as Isla Sorna is within the native range of this species according to FishBase.

Description

The striped bonito grows to 40 inches in length, and is a perciform fish. It has 17 to 18 dorsal spines and 14 to 16 anal soft rays. The dorsal side of its head is a lustrous metallic blue, and the rest of its body is silvery with some darker horizontal striping. Its first dorsal fin is longer than its head and almost connects to the second dorsal fin. The caudal peduncle is very narrow, with six to eight small finlets found on both the top and bottom.

Striped bonito. Image by John E. Randall.

Bonitos are rich in the amino acid lysine, making them a means by which piscivorous dinosaurs could avoid dying due to InGen’s lysine contingency. They also travel into relatively shallow water to feed on crustaceans, during which time the dinosaurs could easily feed on these fish.

Growth

As with most of their relatives, bonitos start out life as planktonic larvae. They gradually develop into adolescent and then adult fish.

Sexual Dimorphism

No sexual dimorphism is known in the striped bonito.

Habitat
Preferred Habitat

The striped bonito inhabits near-coastal waters up to 550 feet deep, but may venture into water as little as three feet deep in search of food.

Isla Nublar

Striped bonitos have not been confirmed near Isla Nublar, though this island is within their native range.

Isla Sorna

In 2001, Dr. Alan Grant and Eric Kirby witnessed a moderately-sized school of bonitos in the large tidal river in the south of Isla Sorna. As these are marine fish that live in waters nearly 550 feet deep, it can be assumed that they are found in the ocean surrounding the Muertes Archipelago. Silver-colored fish which may have been bonitos were seen by Eric Kirby earlier in 2001 off the island’s western coastline.

Known (red) and hypothetical (purple) range of S. orientalis near Isla Sorna, circa 2001
Behavior and Ecology
Daily Activity

In the films, bonitos have only been depicted once during the early hours of the night. In real life, they maintain activity throughout the full daily cycle; most fish do not truly sleep.

Diet and Feeding Behavior

Striped bonitos normally inhabit the ocean, but venture into shallow water to feed. Their diet consists of smaller fish, crustaceans, and small squid.

Social Behavior

Bonitos are shoaling fish, traveling in groups for protection; they may shoal with other types of related fish such as tuna. Despite this, they are not particularly social and do not form attachments with others of their kind. Shoals are capable of group coordination when evading predators, which is observed by Dr. Alan Grant and Eric Kirby. This behavior, called “flashing,” involves the entire school rapidly changing direction in order to reflect light off of their silvery scales to confuse predators and help the fish escape.

Reproduction

Breeding occurs with the monsoon season. Bonitos, as with many fish, spawn by releasing gametes into the water column, and the larvae that develop drift as plankton until they grow large and strong enough to swim on their own. They do not practice parental care.

Vocalizations

Like the majority of fish, bonitos are not capable of vocalizing and have little in the way of communication other than movement.

Ecological Interactions

When in shallow water on Isla Sorna, bonitos are at risk of being preyed upon by piscivorous dinosaurs. A school of bonitos in 2001 was seen fleeing a Spinosaurus, suggesting that this animal preys on them. The bonitos “flash” the spinosaur twice while near the surface, a behavior which in real life helps many kinds of fish escape danger. Other predators which have been confirmed in this same channel include Ceratosaurus and Pteranodon, both of which are believed to feed on fish. These could also be potential threats to native bonitos. The range of Baryonyx on Isla Sorna is not confirmed, but these dinosaurs are also piscivorous and could prey on bonitos.

In Eric Kirby’s account Survivor, he describes a Pteranodon hunting silvery fish in the ocean which may have been bonitos. A cooked fish he describes later attracts a group of Compsognathus and an unidentified medium-sized animal, suggesting that other carnivores may opportunistically eat fish such as bonitos if they get the chance.

Interactions with Humans

Striped bonitos are caught as food by humans in real life, but have not been depicted interacting with humans in the films. In Survivor, Eric Kirby describes having caught a fish from the ocean and cooking it for food, but its species is unconfirmed.