For the past several weeks, we have been witnessing almost all of the Monarch (Danaus plexippus) caterpillars on our milkweed dying from the Nuclear Polyhedron Virus (NPV)! A while ago, we had a large brood of Monarch (Danaus plexippus) caterpillars from a fertile female we had caught back in September. By the time most of the caterpillars had reach fourth and fifth instar, it was becoming a serious pain to keep supplying them with enough fresh milkweed every day. In fact, it was practically impossible. For their size, Monarchs are probably the fastest growing species we have ever witnessed, and the fast they grow the faster the rate that they need to eat. No matter how much milkweed leaves we supplied them, a group of fifty caterpillars or so could plow through it within hours, leaving them starving for the rest of the day while we were gone. By the time the first few caterpillars began to pupate, it had become a disaster. (It was so horrible, we had to end the rearing notes. . .) Simply put, the caterpillar were cannibalizing the prepupae and newly molted (teneral) chrysalises since they were starving and overcrowded. Not a single chrysalis was formed successfully without being eaten. Eventually, we decided that we would have to just release all of the caterpillars on our milkweed in our yard as the simplest solution if we didn't want to have to pick so much milkweed everyday. At first, it was okay. The caterpillars destroyed the plant, but it at least they were full. But a week or so in, the plant became almost completely stripped, the caterpillars were very overcrowded, and it started to rain a lot. Eventually we started seeing caterpillars crawl up to the top of the plant and die from NPV. They would become very limp and black. We're not sure what exactly could have caused the caterpillars to get sick (whether it was correlated to bad rearing conditions outside or if it was just bad luck) but needless to say, it was quite horrifying. Only a few survived. This year is the first time we have ever encountered the NPV virus. We would consider that lucky since it is quite common where winters are mild like in the Bay Area. We don't plan on having to encounter it again, but whether or not we do is anyone's guess since it naturally occurs in the wild as we have seen here. In other words, we can do our best to try to rid of contaminated things right now, but there is no guarantee that the virus won't spring up again next year as it did this year. - 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 |