Editing Luna moth (section)

== Predators and parasites ==

Some species of giant silk moth larvae are known to make clicking noises when attacked by rubbing their serrated mandibles together and can release a regurgitation of distasteful fluids.<ref>{{Cite journal |last=Sourakov |first=Andrei |date=2018-02-24 |title=Size, spines and crochets: defences of luna moth caterpillars against predation by brown anoles |url=https://www.tandfonline.com/doi/full/10.1080/00222933.2018.1439540 |journal=[[Journal of Natural History]] |volume=52 |issue=7–8 |pages=483–490 |doi=10.1080/00222933.2018.1439540 |bibcode=2018JNatH..52..483S |issn=0022-2933|url-access=subscription }}</ref> These clicks are audible to humans and extend into ultrasound frequencies audible to predators. Clicks are thought to be a form of [[Aposematism|aposematic]] warning signaling, made prior to predator-deterring regurgitation of intestinal contents. Luna moth larvae click and regurgitate, with the regurgitated material confirmed as being a predator deterrent against several species.<ref name=Brown2007>{{cite journal |vauthors=Brown SG, Boettner GH, Yack JE |title=Clicking caterpillars: acoustic aposematism in ''Antheraea polyphemus'' and other Bombycoidea |journal=[[The Journal of Experimental Biology]] |volume=210 |issue=Pt 6 |pages=993–1005 |date=2007 |pmid=17337712 |doi=10.1242/jeb.001990 |doi-access=free |bibcode=2007JExpB.210..993B }}</ref>

[[Imago]]s (winged adults) of this and related night-flying ''[[Actias]]'' species, collectively referred to as "moon moths", have long hindwing tails. A "false target" hypothesis holds that the tails evolved to reduce predation risk by bats which use echolocation to locate prey.<ref name=Lee2016>{{cite journal |vauthors=Lee WJ, Moss CF |title=Can the elongated hindwing tails of fluttering moths serve as false sonar targets to divert bat attacks? |journal=[[Journal of the Acoustical Society of America]] |volume=139 |issue=5 |pages=2579–2588 |date=2016 |pmid=27250152 |doi=10.1121/1.4947423 |bibcode=2016ASAJ..139.2579L }}</ref> The moths use the spinning hindwing tails to fool bats into attacking nonessential appendages, with success occurring over 55% of the time.<ref>{{cite journal |last1=Barber |first1=Jesse R. |last2=Leavell |first2=Brian C. |last3=Keener |first3=Adam L. |last4=Breinholt |first4=Jesse W. |last5=Chadwell |first5= Brad A. |last6=McClure |first6=Christopher J. W. |last7=Hill |first7=Geena M. |last8=Kawahara |first8=Akito Y. |name-list-style=amp |date=2015 |title=Moth tails divert bat attack: Evolution of acoustic deflection |journal=[[Proceedings of the National Academy of Sciences of the United States of America]] |volume=112 |issue=9 |pages=2812–2816 |doi=10.1073/pnas.1421926112|pmid=25730869 | pmc=4352808 |bibcode=2015PNAS..112.2812B |doi-access=free }}</ref> Experiments were conducted with Luna moths with intact wings and with the tails removed. With intact wings, a majority of the attacking bats contacted the hindwing tails rather than the body of the moth; only 35% of intact moths were caught versus 81% for those with clipped tails. The results of this experiment support echolocation distortion as an effective countermeasure.<ref name=Barber2015>{{cite journal |vauthors=Barber JR, Leavell BC, Keener AL, Breinholt JW, Chadwell BA, McClure CJ, Hill GM, Kawahara AY |title=Moth tails divert bat attack: evolution of acoustic deflection |journal=Proceedings of the National Academy of Sciences of the United States of America |volume=112 |issue=9 |pages=2812–2816 |date=2015 |pmid=25730869 |doi=10.1073/pnas.1421926112 | pmc=4352808 |bibcode=2015PNAS..112.2812B |doi-access=free }}</ref>

The parasitoid [[Tachinidae|tachinid]] fly ''[[Compsilura concinnata]]'' native to Europe was deliberately introduced to the United States throughout much of the 20th century as a biological control for the [[Lymantria dispar|gypsy moth (''Lymantria dispar'')]] (also known as the "spongy moth").<ref name=Elkinton2004>Multiple sources:
* {{cite web |url=https://www.invasive.org/hostrange/ch2.pdf |title=Chapter 2: The effects of ''Compsilura concinnata'', an introduced generalist tachinid, on non-target species in North America: a cautionary tale. IN: Assessing Host Ranges of Parasitoids and Predators used for Classical Biological Control |vauthors=Elkinton JS, Boettner GH |date=2004 |website=Forest Health Technology Enterprise Team, U.S. Dept. Agriculture |access-date=4 August 2018|archive-url=https://web.archive.org/web/20210916180731/https://www.invasive.org/hostrange/ch2.pdf|archive-date=16 September 2021|url-status=live}} 
* {{cite journal |vauthors=Elkinton JS, Parry D, Boettner GH |title=Implicating an introduced generalist parasitoid in the invasive browntail moth's enigmatic demise |journal=[[Ecology (journal)|Ecology]] |volume=87 |issue=10 |pages=2664–2672 |date=2006 |pmid=17089674 |doi=10.1890/0012-9658(2006)87[2664:iaigpi]2.0.co;2 |url=https://works.bepress.com/cgi/viewcontent.cgi?article=1005&context=joseph_elkinton|access-date=January 7, 2025|via=[[ResearchGate]]}}</ref> Researchers reported that when Luna moth larvae were placed outside for about a week and then collected and returned to the laboratory, four parasitic species emerged, the most common being ''C. concinnata''. The researchers concluded that this parasitoid fly causes collateral damage to Luna moth populations.<ref name=Kellogg2003>Multiple sources: 
* {{cite web |first=Shelly |last=Kellogg |title=Parasitism of silk moths at Sweet Briar College |url=http://www2.sbc.edu/honors/HJ_2002/kellogg.htm |date=July 3, 2002 |access-date=February 8, 2011 |publisher=[[Sweet Briar College]] |work=Honors Journal|archive-url=https://web.archive.org/web/20070827182459/http://www2.sbc.edu/honors/HJ_2002/kellogg.htm|archive-date=August 27, 2007|url-status=dead}} 
*  {{cite journal |vauthors=Kellogg SK, Fink LS, Brower LP |title=Parasitism of native Luna moths, ''Actias luna'' (Lepidoptera: Saturniidae) by the introduced ''Compsilura concinnata'' (Meigen) (Diptera: Tachinidae) in central Virginia, and their hyperparasitism by Trigonalid wasps (Hymenoptera: Trigonalidae) |journal=[[Environmental Entomology]] |volume=32 |issue=5|publisher=[[Entomological Society of America]] and [[Oxford University Press]]|pages=1019–1027|url=https://www.researchgate.net/publication/221959040|doi=10.1603/0046-225X-32.5.1019|access-date=11 January 2024|via=[[ResearchGate]]}}</ref> 

Luna moth larvae have displayed defenses against predators in late instars by developing spines once they reach about 3&nbsp;cm in length. Unlike other species such as ''[[Automeris io]]'', which have chemical defenses much earlier in the larval stage, the Luna moth larvae are left largely defenseless until it reaches this length. However, the absence of a chemical defense allows for the shortening of the larval stage. ''Automeris io'' has a larval stage at least twice as long on average as ''Actias luna'', leaving it vulnerable to [[parasitism]].<ref>{{cite journal |first=Andrei |last=Sourakov |date=2018 |title=Size, spines and crochets: defences of luna moth caterpillars against predation by brown anoles |journal=Journal of Natural History |volume=52 |issue=7–8 |pages=483–490 |doi=10.1080/00222933.2018.1439540|bibcode=2018JNatH..52..483S |s2cid=90239933 }}</ref>