Today when we went to check on our supposedly herbivorous Mexican Bush Katydids (Scudderia mexicana), we were shocked to find that one of the two had been completely eaten by the other! Most Orthoptera are herbivorous. At least, they usually are. Contrary to popular belief, almost all herbivorous animals are capable of carnivory during times in which plants are unavailable. Otherwise their meat-eating counterparts would never have evolved in the first place. For example, there are actually such thing as strictly carnivorous katydids and other Orthoptera that eat other insects and such. The Mexican Bush Katydid (Scudderia mexicana) is not one such example and are normally herbivorous. So, we never expected that we would find one of our Mexican Bush Katydids happily devouring the cadaver of another katydid of the same species. . . . As of two days ago, we still had two living Mexican Bush Katydids nymphs, both of which were wild-caught this year. The first one was much larger, at least one instar ahead of the other one. We had been keeping the two together in the same fruitfly bottle enclosure for as long as we have had them since there seemed to be enough space in there for such small nymphs. But yesterday, the smaller one died a pretty horrible death. The thing must have been resting somewhere along the top of the container when the lid was not screwed closed. When we screwed the lid on not knowing that it was there, its abdomen got crushed very badly. The body was almost cut in two at the site of the injury with guts and body fluid trailing out of the wound. I guess it really would have made sense to remove the body at this time, but we didn't. We just left the poor thing crawl around frantically until it inevitably died from the injury by the end of the day. By today, however, the body was gone, but not because we took it out. It was completely missing with only a few scraps of the legs left at the bottom of the enclosure. The only logical conclusion we could make was that the other katydid have eaten the dead body! Boy, we were surprised. In the past, we had raised a larger number of Mexican Bush Katydids together in a tank where we had also witnessed some form of cannibalism in which the katydids would nibble at each other's legs and wings, often targeting victims that very recently molted. We had assumed that this was due to overcrowding and less-than-optimal living conditions since it is common for insects to eat each other when overcrowded. After all, we had even seen this happen in severely overcrowded, strictly herbivorous walking sticks too. However, overcrowding was not the case here as there were only two of them in a roomy enclosure. The other katydid must have simply took the rare opportunity to feast on a nice pack of fat and protein to supplement its normally leafy diet. After this, we begin to wonder that perhaps the particular species was, indeed, carnivorous to some extent in nature and normally scavenge for and feed on some small dead insects in the wild. Their closest Orthopteran relatives, the crickets, do this all the time. And perhaps by only feeding them an unvaried plant diet, we were depriving them of some nutrients and this was what may have actually encouraged cannibalism, and not any possible overcrowding. In any case, we decided to experiment. We have a hefty supply of fruitflies (Drosophila hydei) fruitflies that we regularly use to feed our European Mantises (Mantis religiosa) so we wanted to see whether the katydid would readily eat them as it had with its roommate. The procudure was simple. Basically, we just lightly crushed a fruitfly with a toothpick or our finger to kill it and draw out the liquid portions. Carefully, without causing alarm, we touched these liquid portions to the katydid's mouthparts to stimulate feeding, but did not forcibly feed the fly when it opened its jaws. What we found was that the katydid really did have an appetite for meat. It gobbled up four whole fruitflies in a row, effortlessly -- even more bestially than the much-touted praying mantis. Because insects do contain a lot of nutrients not available in plants such as chitin and animal protein (more variety of amino acids), we hoped that we had done the katydid a favor and it would grow to be healthier than the vegetarian katydids we had kept in the past. It's certainly nice to think it didn't just eat its roommate cadaver for nothing. - Brian
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Timeline 2012–2017
Albany, California This timeline is a series of daily posts recording our observations on and experiences with various insects in Albany California and surrounding areas, from 2012-2017. Since we did not publish this site until 2016, posts before that were constructed retroactively. Starting in August 2017, we moved to Ithaca, New York; posts from there on can be viewed at Timeline 2017-present: Ithaca, New York. Archives (1,011)
August 2017 (49) July 2017 (121) June 2017 (79) May 2017 (77) April 2017 (91) March 2017 (35) February 2017 (12) January 2017 (10) December 2016 (12) November 2016 (26) October 2016 (49) September 2016 (84) August 2016 (94) July 2016 (99) June 2016 (53) May 2016 (21) April 2016 (4) January 2016 (1) August 2015 (3) July 2015 (3) June 2015 (2) June 2014 (3) May 2014 (1) April 2014 (3) March 2014 (3) December 2013 (2) November 2013 (2) October 2013 (5) September 2013 (11) August 2013 (15) July 2013 (9) June 2013 (5) May 2013 (4) April 2013 (3) March 2013 (2) February 2013 (3) January 2013 (2) December 2012 (2) November 2012 (1) October 2012 (2) September 2012 (2) August 2012 (5) July 2012 (1) June 2012 (1) Authors
![]() ![]() Full Species List (Alphabetical by scientific name) Note: - Not every species we encounter is necessarily presented on this site, rather a selection of those that were of particular interest to us and that we felt were worth documenting. - We can't guarantee that all species have been identified accurately, particularly taxa we are not as familiar with. Lepidoptera Actias luna Adelpha californica Agraulis vanillae Allancastria cerisyi Antheraea mylitta Antheraea polyphemus Anthocharis sara Argema mimosae Attacus atlas Battus philenor hirsuta Bombyx mori Caligo atreus Callosamia promethea Coenonympha tullia california Citheronia regalis Cricula trifenestrata Danaus plexippus Eacles imperialis Erynnis tristis Estigmene acrea Eumorpha achemon Eupackardia calleta Furcula cinereoides Heliconius erato Heliconius hecale Heliconius sapho Heliconius sara Hyalophora cecropia Hyalophora columbia Hyalophora euryalus Hylephila phyleus Hyles lineata Junonia coenia Langia zenzeroides formosana Lophocampa maculata Manduca sexta Morpho peleides Nymphalis antiopa Orgyia vetusta Orthosia hibisci quenquefasciata Pachysphinx modesta Papilio cresphontes Papilio eurymedon Papilio glaucus Papilio machaon oregonius Papilio multicaudata Papilio polyxenes asterius Papilio rumiko Papilio rutulus Papilio zelicaon Phyciodes mylitta Phyciodes pulchella Pieris rapae Plejebus acmon Poanes melane Polites sabuleti Polygonia satyrus Pyrgus communis Rothschildia jacobaeae Samia cynthia advena Samia ricini Smerinthus cerisyi Smerinthus ophthalmica Strymon melinus Trichoplusia ni Uresephita reversalis Vanessa annabella Vanessa atalanta Vanessa cardui Unidentified Lepidoptera Hybrids Papilio glaucus × Papilio rutulus Papilio polyxenes asterius × Papilio zelicaon Orthoptera Melanoplus devastator Phaneroptera nana Pristoceuthophilus pacificus Scudderia mexicana Trimerotropis pallidipennis Phasmatodea Carausius morosus Phyllium giganteum Mantodea Mantis religiosa Phyllocrania paradoxa Hymenoptera Apis mellifera Bombus vosnesenskii Brachymeria ovata Linepithema humile Pediobius sp. Polistes dominula Xylocopa varipuncta Unidentified Diptera Lucilia sericata Unidentified Hemiptera Brochymena sp. Leptoglossus sp. Nezara viridula Odonata Argia vivida Libellula croceipennis Coleoptera Coccinella septempunctata Cycloneda polita Diabrotica undecimpunctata Hippodamia convergens Araneae (Class: Arachnida) Araneus diadematus Phidippus johnsoni |