As we shared last month, surveyor Mike Snow recently submitted the 250,000th survey to our Volunteer Fish Survey Project database. When we asked him to give us some thoughts on what he likes best about REEF, he shared a story about a time when he was buddied with fellow REEF member Greg Jensen, a marine biologist at the University of Washington and author of several reference books, including one on sculpins. Mike and Greg were part of a REEF Advanced Assessment Team project at Saltwater State Park in Washington.

Mike said, “we were slowly swimming together when we spotted a small sculpin whose identity was not instantly obvious, at least to me. I pointed at it, gave an exaggerated shrug, and Greg wrote on his slate "PADDED". Back on the boat during the surface interval, I asked him how he knew that particular fish was a Padded Sculpin, hoping for words of wisdom from someone who's spent much of his career studying these fish. His answer: ‘It just looked like a Padded.'" 

Have you ever experienced this? Turns out, there is a word for it!

If you are a fishwatcher (or birdwatcher, or a field naturalist in general), you know that sometimes you just know the identity of a species. There’s nothing in particular that you can point to if someone asks how you know, it just is. In the birdwatching world, this concept has been well written about, and is commonly known as GISS or jizz. GISS is an acronym for “general impression of size and shape” and originated in the military as a way to identify aircraft. The origin of “jizz” is less clear, but likely is related to the German word gestalt, which means a complete shape or form. Jizz first appeared in an Irish natural history newspaper column in 1921, predating GISS, which was first used in World War II. 

When you are fishwatching by GISS or jizz, you are using the whole picture; the combined impression of key characteristics, the setting, and even just the vibe. Of course, there is size and color pattern, but also behavior, swimming style, habitat, and how the fish is positioned in its habitat. This ‘it just is' feeling is greatly enhanced by the power of your first-hand knowledge and experience in the water. The more time you spend watching fishes, the better you get at knowing which traits to focus on. Even if you don’t know offhand the exact species, it will help you decide the fish family as a starting point. It may seem a bit messy and imprecise, but the “jizz of a fish” can be quite effective and surprisingly accurate, especially with experience. 

If you want to learn more about this topic, check out this article or this scientific paper. And a shout out to active REEF surveyor, Chuck Curry, for first introducting the author of this article to this concept!