An r-strategist is a species categorized by its abilities to reproduce quickly, generally small size, lack of parental care, high death rates, unstable populations, etc. R-strategists can be bacteria, insects, etc. For example, fish lay hundreds of eggs (which they don’t care for individually unlike in the case of a k-strategists) that quickly mature into full-grown fish and (compared to k-strategists) die quickly. R-strategists almost always find a way to regenerate their population numbers when faced with a time with significant population decrease. R-strategists can adapt to a variety of environments and usually live in a diverse range of environmental conditions. The fish pictured above are r-strategists.