Unfortunate Mate Choice

Extinction by hybridization is a very real threat to many species. One of them is the Mexican golden trout (Oncorhynchus chrysogaster) a small, beautiful salmonid endemic to Mexico. It's home waters have been flooded by introduced rainbow trout (O. mykiss).

The two trout interbreed and produce hybrid offspring. With rainbow trout being released by the millions, most of the offspring are bound to be hybrids. The unfortunate thing is, rainbow trout are not well adapted to the warm waters in Mexico, and their population will slowly wither away, unable to sustain itself. There's a risk they will take the golden trout with it, it's genes too diluted in the population of hybrids to help much in adapting.

So here's the hybridization in action: a large male rainbow trout spawning with a much smaller female Mexican golden trout.

An illustration I made for Helsingin Sanomat, a Finnish daily newspaper. Black markers and digital painting.