The Tiny Fish Few Divers Ever See: Rare Saddleback Gunnel Pair Found Living Inside a Beer Bottle

“Among the hidden rewards of muck diving in British Columbia is stumbling upon small dramas playing out in the shadows beneath a dock. On this dive, a bonded pair of saddleback gunnels had claimed a classic Canadian stubby beer bottle as their refuge.

Saddleback gunnels are known for forming long‑term pair bonds, and they often return to the same shelter year after year.

It was a small scene, but a telling one: even discarded trash on the seafloor can provide shelter to marne life… and even the most unassuming fish can reveal complex behaviours when given a place to call home.” Jett Britnell

The saddleback gunnel (Pholis ornata), frequently referred to as the saddled blenny, is a coastal marine fish from the gunnel family (Pholidae). These ray-finned fish inhabit the shallow, nearshore environments of the eastern North Pacific Ocean.

Physically, this species is characterized by an elongated dorsal fin containing 74 to 79 spines, complemented by an anal fin configured with 2 spines and 35 to 38 soft rays. It features a distinctively rounded tail fin alongside minuscule pelvic fins, and individuals can reach a maximum recorded length of 30 centimeters (12 inches). Visually, the fish is defined by a series of 12 or 13 dark, saddle-shaped patches lining its back, as well as a pattern of alternating light and dark bands that branch out directly from its eyes.

In terms of diet, these gunnels prey on minor mollusks and small crustaceans. Once reproduction is complete, both parents share the responsibility of protecting the cluster of eggs. By the time the early spring arrives, the young fish enter their initial post-larval phase, measuring roughly 18 to 20 millimeters in length.

Geographically, the range of this species extends from Vancouver Island southward to Santa Barbara County, California. These fish occupy coastal zones and tidal estuaries at depths down to 50 meters (164 feet), typically favoring muddy bottoms densely covered with marine algae and seagrass beds. Because they remain hidden within shelters for the majority of the day and are highly skittish even after dark, encounters with divers are exceedingly rare.

The Saddleback Gunnel is currently categorized as a species of Least Concern. While coastal pollution likely influences their populations, further scientific investigation is required to fully quantify how environmental degradation and climate change impact the species. At present, there are no targeted conservation initiatives or protective measures established for this fish.