ENVIRONMENT ASSESSMENT REPORT FOR Aedes koreicus

1.

a. Family: Culicidae

b. Genus: Ochlerotatus (the genus Ochlerotatus was recently elevated from a subgenus of Aedes. Many biologists in Australia still use the Aedes genus to avoid confusion, since decades of scientific literature refer to medically important mosquitoes with the former genus name Aedes, so in the report I will refer to Aedes koreicus).

c. : koreicus

d. There are no known subspecies of Ae. koreicus.

e. Edwards, F.W. 1917. Bull. Ent. Res. vii: 212-213.

f. No common names are yet known for this species.

g. This is not a genetically-modified organism (GMO).

2. Status of Aedes koreicus under CITES

Aedes koreicus is listed neither on Appendix I or II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).

3. Ecology of Aedes koreicus

a) The longevity of Aedes koreicus is unknown. A closely related species, , is known to have a half-life in captivity of 15-35 days, depending on food available and presence of competing species, with a maximum age in captivity of 40-75 days (Alto 2009). Longevity in the wild is not known, but for mosquitoes, it is usually shorter than longevity in captivity.

b) Size and weight of mosquitoes will differ depending on temperature, food availability and presence of competitors in their larval habitat. However, based on collected samples in Italy, the range of lengths (from antenna to tip of abdomen) is 6.8 – 7.4 mm for adult females (see Figure 1 below for typical female) and 5.3 – 6.9 mm for males. The dry weight of specimens is 0.1-0.2 mg for males and 0.5-0.6 mg for females (measured by S. Ciocchetta).

Figure 1. Collected Ae. koreicus female (left) and male (right) with antennal, thoracic and abdominal lengths measured (collected in Verona, Italy, photos: F. Montarsi). c) Male and female mosquitoes are quite easy to differentiate, based on antennae (males have much more feathery antenna, see photos).

Ae. koreicus adults have some superficial resemblance to a few native Australian mosquitoes (e.g. Aedes notoscriptus, Ae. palmarum) and to invasive species Ae. aegypti and Ae. albopictus. However, the combination of golden hairs on the thorax as well as the distinctive vertical stripe along the scutum flanked by two shorter vertical stripes (see Figures 2A-2B below) makes it relatively easy to identify this species with at most a small amount of training.

Also photographs of adults are available (see Figure 2 below), we do not have photos of the larvae or pupae at this time.

Figure 2. A) Adult female (photo: A. Drago) and B) adult male of Aedes koreicus (photo: F. Montarsi). d) The native range of Ae. koreicus is Korea, China, Japan (Hsiao and Bohart 1946) and Russia. Miyagi (Miyagi 1971) reported finding larvae in artificial containers near houses in Korea. Miles (Miles 1964) reported finding larvae in brackish seaside pools in the far-eastern (former) USSR. Kim et al (Kim 2005) reported finding Ae. koreicus larvae in tyres and rock pools in Korea.

Population limiting influences for Ae. koreicus would include habitat availability (rock pools, artificial containers, used tyres) and predation (Australia has a native predatory mosquito Toxorhynchites speciosus, as well as other invertebrate predators such as backswimmers, that prey on mosquito larvae found in containers and tyres). e) Aedes koreicus is not known to be migratory. f) Aedes koreicus eggs are able to survive freezing during the winter months. g) Larval, pupal and adult stages of Ae. koreicus breathe air (the aquatic stages breathe air at the water surface using a siphon). h) Habitat requirements: a. Physical parameters: i. Salinity: the aquatic larvae of Ae. koreicus are most commonly found in temperate climates in containers filled with rain water, but they have also been found in brackish rock pools. ii. Since mosquito larvae breathe air through a siphon, they do not necessarily need well-oxygenated water. That said, the requirements for water quality and oxygen content have not been evaluated for Ae. koreicus. iii. pH: The full range of pH that Ae. koreicus can tolerate has not been investigated. iv. Temperature: Precise temperature evaluations have not been done for Ae. koreicus, but the species is known to live in temperate climates in Korea, Japan, Russia, Belgium and northern Italy. Its eggs are able to survive freezing during the winter. b. Climate: Ae. koreicus is known to live in temperate climates, and the eggs can survive freezing during the winter. It is unknown how Ae. koreicus would fare in subtropical and tropical climates. c. Aedes koreicus larvae have been found in rock pools, used tyres and other artificial containers. d. Aedes koreicus has not been found to nest in marshes, swamps, estuaries, lakes, ponds, dams, rivers, channels, streams, banks of water bodies, coastal beaches or sand dunes. i) Social behaviour. Mosquitoes tend to be for the most part solitary. Larvae from the same egg batch would cohabit in a water source, but that wouldn’t be considered “social”. Adult males of some species form swarms in order to attract females, but the mating behaviour of Aedes koreicus has not been studied. j) Mosquitoes are not known to be territorial or aggressive to other species, beyond females seeking out warm-blooded hosts to blood feed. k) Injury and harm to humans: Female Aedes koreicus can bite humans, which can cause an allergic response including reddening, itchiness and slight swelling at the bite site. Their status as a disease vector is

not well known. Japanese encephalitis virus was detected in some collected specimens (Miles 1964).

Reproductive Biology of Aedes koreicus

a) The reproductive biology of Ae. koreicus has not been studied, but most adult male mosquitoes are sexually mature by the second day of adulthood, and most females mosquitoes by the third day of adulthood. b) For most blood-feeding mosquito species, after the female mates, she requires a blood meal to gain the protein needed to produce eggs. Most mated females will lay eggs three or four days after a successful blood meal. Some mosquitoes are autogenous, meaning they do not require a blood meal to lay eggs. It is unknown if Ae. koreicus is autogenous; however, closely related species (e.g. Ae. notoscriptus, Ae. japonicus) are not autogenous, so it is unlikely.

Breeding sites for mosquitoes are almost always stagnant water. For Ae. koreicus, brackish rock pools, used tyres and artificial containers around buildings are all suitable habitats.

c) It is not known how often Aedes koreicus breeds. d) Not applicable (these are not sessile aquatic invertebrates). e) Mosquitoes have never been known to change sex. f) Hybridization involving Aedes koreicus has not been observed. It is notable that they have not been known to hybridize with the closely related Ochlerotatus japonicus species complex (Cameron 2010) g) It is unknown if Ae. koreicus can hybridise with Australian native species, but considering that they haven’t been known to hybridise with closely-related Asian species (see above), it is not likely. h) All mosquitoes are single-sexed. No hermaphrodites have been reported. 4. Feral Populations a) Aedes koreicus has been found to have established breeding populations in Belgium (Versteirt 2012) and northern Italy (Capelli 2011).

b) Despite the fact that it is known to bite humans, Ae. koreicus is not known to be a pest in its known or introduced habitat. There are no eradication programs.

c) The only known introductions of Ae. koreicus into other countries are in Belgium and Italy (see above). Means of entry is unknown, though imported tyres or plant cuttings are the most likely routes (Cappelli et al 2011).

5. Environmental risk assessments of the species

No risk assessment has been carried out in Australia or overseas for Ae. koreicus.

6. Likelihood that Aedes koreicus could establish a breeding population in Australia a) The diet of adult and larval Ae. koreicus is very similar to that of native Australian mosquitoes: aquatic detritus, algae and microorganisms for the larvae, and nectar and bird/mammal blood for the adults. Ae. koreicus would be able to find food in Australia. b) Since these mosquitoes breed in artificial containers such as plant pots, used tyres and bird baths, it would be possible for them to continue breeding even during a drought. Eggs of all Aedes mosquitoes can survive in a dry state for up to a few months until triggered to hatch by rain. In temperate areas of Australia, the eggs are sufficiently cold-tolerant to survive the winter.

c) Aedes koreicus seems to be well-adapted to human modified habitat. They have been found breeding in sewers, artificial containers and used tyres.

d) Mosquitoes can lay over a hundred eggs in their lifetime, so that could increase the likelihood of Ae. koreicus to establish. This is nothing unique to Ae. koreicus, however.

e) The most likely limiting influence on Aedes koreicus in Australia would be competition from native mosquitoes. Ae. notoscriptus, for instance, is a container breeding mosquito present all over Australia, so it would compete with Ae. koreicus over its entire range.

f) Since Aedes koreicus is not present in Australia, any imported individuals should be limited to research facilities with appropriate quarantine facilities and experienced staff to prevent their escape into the environment. The establishment of feral populations in Australia would therefore be extremely unlikely.

7. Potential Impact of Aedes koreicus Should it Become Established in Australia a) Aedes koreicus fills a similar niche as a number of native Australian container-breeding mosquitoes, most notably Ae. notoscriptus. They would be expected to compete for larval habitats and food (i.e. aquatic microorganisms and detritus) should Ae. koreicus be released into the environment.

b) Aedes koreicus adult females are known to bite humans and sea birds in Russia (Miles 1964). They may bite other mammal and birds species, but this has not yet been observed or evaluated. They may bite domestic livestock, but this has not yet been observed. Mosquito bites can cause an allergic response including reddening, itchiness and swelling around the site of the bite. Aedes koreicus has been reported to be able to be infected with Japanese encephalitis virus (Miles 1964) and dog heartworm (Ludlam et al 1970).

c) Impacts on habitat and local environments: a) This species will not reduce ground vegetation cover. b) This species does not dig burrows.

c) This species has not been known to damage native ’ habitats, natural communities, native plants, forestry or agriculture. d) This species is highly unlikely to inhibit tree seedling regeneration. e) This species is highly unlikely to spread weeds. d) Behaviours that cause environmental degradation a) Aedes koreicus is not known to exhibit any behaviours that cause physical disturbance to the environment. b) This species is not known to eat or disturb wetlands or wetland vegetation. c) This species is not known to cause pollution of water bodies. d) The known habitats of Aedes koreicus are artificial containers, used tyres, and rock pools. These are not particularly sensitive environments in general, and there is no indication they would be aversely affected by Ae. koreicus. e. Impacts on primary industries a) Aedes koreicus is not known to cause damage to livestock, poultry, etc., although it may bite livestock or poultry that are near breeding areas. This mosquito is not know to transmit any livestock or poultry diseases, and bites are unlikely to have a serious impact (e.g. milk production, egg laying, general health, etc.) unless there were large numbers of biting mosquitoes. b) This species is not expected to eat or damage any plants or plant parts. c) This species is not expected to compete with livestock. d) This species is not expected to have a negative impact on tree plantations/silvicultural activities in any way. f) Damage to property a) Aedes koreicus has not been known to and is not expected to deface or physically damage buildings, either through physical damage or depositing excrement. b) This species is not known to damage fences. c) This species is not known to damage equipment. g) Aedes koreicus could potentially be a social nuisance by biting if it is prevalent near humans in large numbers. This is no different than the social nuisance already presented by native Australian mosquitoes. h) Potentially harmful characteristics of Aedes koreicus: a) Ae. koreicus is known to bite humans and feed on blood. This can cause itching and swelling at the site of the bite, which can be treated with any one of a number of ointments or natural treatments. Typical mosquito repellents available in Australia would be expected to be effective against Aedes koreicus as well. Ae. koreicus has been reported as a vector of Japanese Encephalitis virus (JEV) (Miles 1964). Whether this mosquito can transmit JEV in nature has not been well investigated. There is a JEV vaccine available. b) Ae. koreicus has been known to bite people. This can cause itching and swelling at the site of the bite, which can be treated with any one of a number of ointments or natural treatments. No further injury has ever been reported from this species to humans. Aedes koreicus has been reported to be able to be infected with Japanese encephalitis virus (Miles 1964) and dog heartworm (Ludlam et al 1970).

c) Ae. koreicus has been reported as carrying of JEV (see above), although whether it can transmit the virus to humans has yet to be investigated. Other viruses have not yet been tested. In a review by Ludlam et al. (1970), Ae. koreicus was listed as a potential vector of dog heartworm . Research needs to be done to see if this species could transmit other viruses in Australia if it became established.

8. Conditions or Restrictions to Reduce Any Potential Negative Impacts of Aedes koreicus Unintentional import of Ae. koreicus into Australia would most likely be in the form of eggs or larvae in containers of water. This is a similar ecology to the invasive Asian tiger mosquito Aedes albopictus. Australia has an eradication program in place for Ae. albopictus, which was put into action as recently as December 2012, when Ae. albopictus were discovered in two greenhouses outside of Melbourne and subsequently eradicated (http://www.daff.gov.au/about/media-centre/dept-releases/2012/asian-tiger- mosquito-in-melbourne). Restrictions placed on import of Aedes koreicus should include limiting importation to research use only, in addition to the requirements for an import permit and quarantine facilities.

9. Summary of Proposed Activity a) Our laboratory (Mosquito Control Lab, Queensland Institute of Medical Research), is collaborating with Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe) in Verona, Italy, to assess the risk of this newly discovered invasive mosquito for Europe and Australia. QIMR has the necessary high containment quarantine facilities, resources and expertise to evaluate the ability of this mosquito to transmit medically important viruses such as dengue, Ross River virus, Murray Valley encephalitis, Barmah Forest virus, chikungunya and West Nile. After these experiments are completed, we will have a more accurate risk assessment for this species, and any remaining mosquitoes will be destroyed.

b) We would import about 5000 eggs. Aedes eggs can be laid on paper towels or similar surfaces, dried out, then hatched up to a couple of months later.

c) The males don’t particularly interact. They may form mating swarms to facilitate attracting females, but the mating behaviour of this species has not been studied. No segregation is required.

d) The purpose of importing Ae. koreicus is not for breeding.

e) The mosquito will be used for research purposes only. This may include genetic studies, protein studies and laboratory behaviour/physiology studies. We recommend the import of this species be limited to research purposes only.

f) Our collaborators at IZSVe are planning to establish an Ae. koreicus captive colony from mosquitoes captured around the city by (northern hemisphere) summer. They will send us eggs from that colony.

10. Guidelines on How Species Should Be Kept

a) Aedes koreicus will be shipped as eggs in approved IATA packaging by an approved courier. b) Mosquitoes are typically kept in secure 30 cm3 cages with a density of several hundred individuals per cage, and secondarily contained in a stainless steel cabinet enclosed with stainless steel mesh within an insectary. Mosquitoes not native to Australia will be contained within a quarantine approved insectary. c) Mosquitoes typically hatch in a 50/50 male: female ratio. Since females live longer than males, a colony with overlapping generations tends to have more females than males. Breeding is easily controlled by withholding of oviposition sites within the cage, so populations within the cage are easily maintained. d) Aedes koreicus will be kept in a quarantine-approved insectary at the Queensland Institute of Medical Research (QIMR) in Herston, Queensland. They will be housed in standard 30.5 x 30.5 x 30 cm cages from BioQuip (http://www.bioquip.com/search/DispProduct.asp?pid=1450A). These cages will be secondarily contained within a stainless steel 1.5 m x 41 cm shelving unit enclosed in 100 micron stainless steel mesh. These mosquitoes will be used for research only, and destroyed when the research project is complete. e) Keeping mosquitoes in an enclosed cage does not raise any welfare issues for the mosquitoes.

11. State/Territory Controls There are no Commonwealth, state or territory legislative controls on Aedes koreicus other than quarantine legislation. Aedes koreicus is required to be imported with an appropriate import permit and will be contained in a quarantine approved insectary QIMR will meet any other conditions included on the import permit.

12. Conditions/Restrictions Aedes koreicus should be approved for import into Australia subject to the condition it is used for research only in high security facilities. The imported mosquitoes will also be handled by experienced staff that have completed quarantine accredited training. The Queensland Institute of Medical Research (QIMR) already holds exotic mosquitoes so has experience in high containment requirement.

References Cited

Alto, B. W. (2009). "Interspecific larval competition between invasive Aedes japonicus and native Ae. triseriatus (Diptera: Culicidae) and adult longevity." Journal of Medical Entomology 48(2): 232-242.

Cameron, E. C., Wilkerson, R.C., Mogi, M., Miyagi, I., Toma, T., Kim, H.C., Fonseca, D.M. (2010). "Molecular phylogenetics of Aedes japonicus, a disease vector that recently invaded Western Europe, North America, and the Hawaiian Islands." Journal of Medical Entomology 47(4): 527-535.

Capelli, G., Drago, A., Martini, S., Montarsi, F., Soppelsa, M., Delai, N., Ravagnan, S., Mazzon, L., Schaffner, F., Mathis, A., Di Luca, M., Romi, R., Russo, F. (2011). "First report in Italy of the exotic mosquito species Aedes (Finlaya) koreicus, a potential vector of and filariae." Parasites and Vectors 4(188).

Kim, H. C., Wilkerson, R.C., Pecor, J.E., Lee, W.J., Lee, J.S., O'Guinn, M.L., Klein, T.A. (2005). "New records and reference collection of mosquitoes (Diptera: Culicidae) on Jeju Island, Republic of Korea." Entomological Research 35(1): 55-66.

Miles, J. A. R. (1964). "Some ecological aspects of the problem of -borne viruses in the Western Pacific and south-east Asia regions." Bulletin of the World Health Organization 30: 197-210.

Miyagi, I. (1971). "Notes on the Aedes (Finlaya) chrysolineatus subgroup in Japan and Korea (Diptera: Culicidae)." Tropical Medicine 13(3): 141-151.

Versteirt, V., Pecor, J.E., Fonseca, D.M., Coosemans, M., Van Bortel, W. (2012). "Confirmation of Aedes koreicus (Diptera: Culicidae) in Belgium and description of morphological differences between Korean and Belgian specimens validated by molecular identification." Zootaxa 3191: 21-32.