Does Color Matter when Cammo Rules?

I’ve made the case that color matters to surfperch in the wild and I demonstrated this by showing that given a choice, silver surfperch, Hyperprosopon ellipticum, take orange colored lures at rates higher than you would expect by chance alone. If you want to read about why color might matter to surfperch, and the details of my experiment, check out Choices, Choices…Everywhere.

While I was exploring lure color preference in silver surfperch, plenty of staghorn sculpins, Leptocottus armatus, also made choices about my lures. I show the results below. As you can see from the the photo above, staghorns blend into the sandy background on outer shores beaches. They have small eyes, the sexes are similar, they have external fertilization, and neither sex shows off any colorful adornments such as bright spots or fins. So they are a very different from the surfperches they share the beaches with from June to September. If you want to read more about staghorns, check out A Camoflaged Big-mouth on Summer Shores and Cammo Rules!

Here are the lures I presented to fish in the wild: black, yellow, red, orange, and pumpkinseed (the brown lure with black specks).

And there was one other choice, bait, a chunk of bay ghost shrimp, Neotrypaea californiensis. These crustaceans are commonly sold as bait where they are known as sand shrimp. As far as I know, all fish love them.

Fifty-eight staghorns committed to my presentations and, superficially, the results look similar to what we saw with the silver surfperch. One exception is that bait did a lot better with staghorns than with silvers. With their large gape and attitude about food this isn’t a surprise. Pumpkinseed and orange lures were slightly over-represented and black and red lures were under-represented compared to what we would expect by chance. However, the signal isn’t very strong and I can’t really reject the idea that all of this is quite independent of color.

Is the weak signal a sign that there is no lure preference in staghorns? Or was there something else about my design that might have made any preference hard to detect? To test this I repeated my experiment on a smaller scale with several refinements. First, I improved the presentation, removing any beads or other adornments near the lures that might have influenced choice. Next, I got rid of bait…what a silly idea that was. I also standardized some things about how long lures were in the water and how I recorded notes, and finally, I swapped out the flecked pumpkinseed lure for a very similar brown (flesh-colored) lure without flecks.

In my refined experiment black is still under-represented but this time red is over-represented compared to the chance expectation, but once again the signal is not strong and I can’t reject the idea that the choices staghorns are making are independent of color. Other than the apparent dislike of black lures in both experiments, the patterns of lure color choice seem to be weak and unstable. Thus, staghorns seem to lack the orange bias seen in silver surfperch and maybe color doesn’t matter when cammo rules. How do these results compare to your predictions about lure choice by staghorns?

Note: I updated the images and lightly edited the text on October 7, 2017. If you like the color preference stuff, you might be interested in To Bite, or Not to Bite, which follows up on the work presented here.