So people can better understand the bluegill(Lepomis macrochirus)and its many "varieties", let's take a closer look at the different bluegills.
Biologists may recognize as many as 5 or 6 different subspecies of bluegill. In order to understand what this means, one has to understand what a subspecies is. A subspecies (commonly abbreviated subsp. or ssp.) in biological classification is a taxonomic rank lesser than species. All known organisms are given scientific names. This system is the Linnaean Taxonomic Rank. Even we humans have a scientific name, Homo sapiens
. Homo being the genus name and sapiens being the species name for humans. Those are the two taxonomic levels used for identification purposes. However, all organisms have five other taxonomic levels. In humans, it goes like this. Kingdom-Animalia, Phylum-Chordata, Class-Mammalia, Order-Primates, Family-Hominidae, then onto the scientific name with Genus-Homo and Species-Sapiens. It’s after the level species we get the subspecies level. Humans have no scientifically recognized subspecies. However, bluegills do as do many other species like whitetail deer(with as many as 38 subspecies) to even Canada geese(with as many as 11 subspecies).
A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all(humans) or two or more(whitetail deer, Canada goose), never just one. So for say humans our scientific name is Homo sapiens
and that is it. With the whitetail deer for example, its scientific name is Odocoileus virginianus
with for example the southern whitetail deer being Odocoileus virginianus virginianus
. The species and subspecies name is the same for the southern whitetail because it was the first subspecies to be named by science. The Key deer, a subspecies of whitetail deer native to the Florida Keys has a scientific name of Odocoileus virginianus clavium
. In scientific literature, you will often see the genus and then the species name abbreviated down to just the first letter of the word after it has been mentioned one time. So since the southern whitetail deer has already been mentioned, if I mentioned it further it would be written as O. v. virginianus
Organisms that belong to different subspecies of the same species are generally capable of interbreeding and producing fertile offspring. However they often do not interbreed in nature due to geographic isolation(large mountains or wide bodies of water separating them for example) or other factors. The differences between subspecies are usually less distinct than the differences between species, but more distinct than the differences between breeds or strains(breeds and strains are often man made and not formed through natural evolution, an example of a breed in a bluegill could be the Condello bluegill, selectively bred for acceptance of pellets and fast growth rates). The characteristics attributed to subspecies generally have evolved as a result of geographical distribution or isolation.
That last sentence is key to understanding how the coppernose bluegill came about. First off, let's review the different subspecies of bluegill. Most biologists recognize at least the two most common subspecies of bluegill. These would be the two we most commonly write about.
They would be the northern or "native" bluegill(L. m. macrochirus
) and the coppernose or Florida bluegill(L. m. mystacalis
). The northern bluegill is native from approximately the Apalachicola River drainage in the panhandle of Florida to eastern Texas. It then ranges to the far northern reaches of the Mississippi River drainage into southern Canada. It ranges as far east as western New York in the drainages that flow into the Great Lakes and then ranges south along the continental divide back down to the Florida panhandle. It has also been extensively introduced into the Atlantic drainages from New Hampshire south where no bluegill subspecies was native.
Now here is where the fun and disagreements among biologists begins. The coppernose bluegill is native to all of peninsular Florida from approximately the Suwannee River drainage south along the Gulf coast to the southern tip by the Keys. It is also native from the southern tip up the east coast to, well this is where the argument begins. Some biologists believe its range ends around the St. Mary's River drainage at the border with Georgia. Other biologists believe that from that point north is a new subspecies, the eastern bluegill (L. m. purpurescens
). The eastern bluegill is native as far north as the Pee Dee River drainage in South Carolina and the Yadkin River drainage in North Carolina. The eastern bluegill is only native to Atlantic drainages in the southeastern states, you cross the continental divide(Appalachian Mountains) and you then get into the Mississippi drainage where the northern bluegill is native or Gulf of Mexico drainages where the eastern bluegill is not native either. Most biologist do not recognize the eastern bluegill as a separate subspecies though and believe the coppernose or Florida bluegill simply goes all the way up the east coast to the Pee Dee and Yadkin River drainages. Some biologists believe there may even be more subspecies within peninsular Florida itself further dividing the coppernose bluegill into more subspecies. There is a huge variance between the bluegills in the different drainages within Florida. Whether these differences are enough to create a separate subspecies is up for debate. No new subspecies have been named as of yet though.
There is a natural introgression area generally thought to be in the area of the Suwannee River drainage west to the Apalachicola River drainage in the Florida panhandle. The northern subspecies and Florida(coppernose) subspecies were separated for about 2.3 million years. The event believed to have split the parental species apart and to cause the divergence was the repeated glaciations of North America. With the end of the last glacial period the now distinct subspecies were able to come back in contact in the above mentioned drainages.
Within this introegression area is another unlisted and possibly distinct subspecies of bluegill commonly referred to as the “hand painted” bluegill. Because it is not a scientifically recognized subspecies it has no subspecies name as of yet. The hand painted bluegill is endemic to the Apalachicola River drainage. It is a strikingly colored bluegill. It is bright red on the top third of its sides fading to more normal bluegill coloration on the rest of its sides. The breast area is bright red as well. Then the most interesting characteristic of the hand painted bluegill are large blotches of black on its sides. Most biologists do not believe it is the result of intergrades between the Florida(coppernose) and northern bluegill but rather some other events have created this unique bluegill. The Apalachicola River is a very special river in many ways.
The last and yes I’ll say it, least bluegill is the western bluegill(L. m. speciosus). I say least as it is basically a pygmy when compared to the other subspecies of bluegill. When grown in the same conditions as northern bluegill it grows slower and attains a much smaller maximum size. It is native to central Texas into western Texas, south into northern Mexico and north into southern Oklahoma. There are probably few pure western bluegills anymore. Extensive stocking of northern and coppernose bluegills within its native range have most likely caused numerous crosses and backcrosses.
In a recent thread Bluegill Varieties Interbreeding
it was asked whether northern and coppernose bluegills would successfully cross with each other. They are the same species and thus are defined to be able to spawn successfully and produce fertile offspring. This is in fact the case. As part of the spawning behavior of bluegills, males do a “spin up” when females are present almost like a dance to attract them and entice them to lay their eggs in his nest. Some scientific research in controlled environments has shown male coppernose bluegills will spin up for female coppernose bluegills quite readily but rarely will they spin up for female northern bluegills. However, male northern bluegills will spin up for either subspecies. Whether this holds true in a wild pond environment is unknown.
Well, if you read this far you must be a bluegill nut! Hopefully you enjoyed the history of the mighty bluegill. Now get to growing some monsters in your pond!