This is a question we occasionally receive in our enquiry inbox. in fact, bloodworms and red mosquito larvae are exactly the same thing! Jazz trumpeter Louis Armstrong and jazz singer Ella Fitzgerald once sang a famous duet ‘Let’s Call the Whole Thing Off’ written by Ira Gershwin. It deals with the same matter: one and the same thing being called or pronounced differently by people having a different cultural or ethnic background.  

   The term bloodworm is given to a number of completely different, non-related species. In the pet food industry ‘bloodworms’ refers to the aquatic, larval stage of the (non-biting) midge genus Chironomus. Midges belong to the insect order of the Diptera, an extremely large order within the class Insecta containing over 100,000 described species[1] . The order contains the true flies, mosquitoes & midges. Diptera in Greek means ‘two-winged’ and refers to the fact that these insects only have 1 pair of membranous wings. ‘Dipterans’, as the members of the order are called, include black flies, brine flies, crane flies, dance flies, deer flies, fruit flies, hoverflies, horse flies, leaf-miner flies, robber flies, other flies, biting as well as non-biting midges, fungus gnats, gall midges, all mosquito species etc. Ok, so all flies? Nope, stoneflies for example are not real flies but belong to the order Plecoptera (Greek for ‘folding wings’) whilst damselflies or dragonflies belong to the order Odonata (meaning ‘having teeth’). Mayflies don’t belong to the ‘real flies’ either and neither do fireflies, which are actually beetles.

   In the field of professional aquaculture the term ‘blood-worms’ used to refer mainly to the genus Glycera, which is a marine polychaete (a bristle worm). And marine anglers taking their hobby seriously also think of Glycera when talking about ‘bloodworms’. However, as the cost of fishmeal has been steadily increasing for nearly 2 decades whilst prices of farmed fish have mostly gone down, fish breeders have been looking for more economical protein sources able to replace fishmeal. This, plus the need to improve the environmental sustainability of aquaculture (why use such a valuable protein source as fishmeal for feeding fish, shrimp or ornamental fish whilst it could be used for feeding people?), has put bloodworms on the table as a potential fishmeal replacement. Please look here for a summary of the nutritional value of bloodworms. Tropical fish breeders in Southeast Asia for example have been increasingly using more natural protein sources such as chironomids and Daphnia for well over a decade.

   In our case, the bloodworms we offer for sale are either instar 2, instar 3 or instar 4 larvae of the non-biting midge species Chironomus plumosus. More information about the larval life stages and bloodworm size can be found here.

   At the end of the 80’ties of the last century, our investor (San Francisco Bay Brand, Inc.) started importing frozen bloodworms from Europe and offering these for sale in the Americas (North & South America) and in Japan. That was after our current general manager, president and 2nd generation owner Andy Schmidt, encountered frozen, blistered and bagged bloodworms on display when taking part in the biennial tradeshow ‘Interzoo’ in Nürnberg, Federal Republic of Germany.

   In the German language bloodworms are called Rote Mückenlarven, which literally means ‘red mosquito larvae’. The adults are commonly called Zuckmücken (non-biting mosquitos), Tanz-mücken (dancing mosquitoes) or Schwarm-mücken (swarming mosquitos).

   In the Dutch language bloodworms have two common names: rode muggenlarven, literally meaning ‘red mosquito larvae’ and ver de vase, the latter being a borrowed term from the French language and meaning ‘mud worm’. The adults are either called dansmuggen (dancing mosquito’s), because during the mating season numerous males come together to form swarms in which the males seemingly make ‘erroneous’ flying movements looking for a partner; either vedermuggen (feathered mosquito’s) because adult males have 2 large featherlike antennas with which they can pick up signals sent out by females.

   In Dutch or French speaking countries the term 'ver de vase' has been used for over a century and it still is very commonly used when entering a pet shop for purchasing live larval midges before going fishing. One typically purchases an ounce or so and receives the live worms wrapped in wet newspaper. When stored in a cool, moist place, these live ‘ver de vase’ will stay alive for up to a week.

   So why are bloodworms called red mosquito larvae in most European countries, although they are not mosquito larvae? Because adult midges very much resemble mosquito’s and a hundred years ago common people more than likely did have nor the time, nor the knowledge, to make a distinction between a midge and a mosquito. But one could also ask: why are midge larvae called bloodworms whilst they are not worms? Well, because the larvae look like worms. And so we arrive back at Satchmo and the first Lady of Song singing ‘Let’s Call the Whole Thing Off’ …