The Effects of Climate Change on Pest Problems Moray Anderson Technical Director, Killgerm Group. The Effects of Climate Change on Pest Problems

Climate change Examples to be discussed: New diseases associating with established insect species West Nile Virus. New invasive insect species New diseases associated with these. Re-emergence of “old” pest species Microclimatic changes.

Climate change What is predicted ? Universal increase in temperatures Insect metabolism – temperature dependant Small changes can have significant effects Lengthening of breeding seasons Changes in insect distribution geographically

Cimex lectularius – Eggs Bedbug life cycle. Cimex lectularius – Eggs   Temperature (°C) Egg hatching time (days) 13 49 15 34 18 21 22 12 27 5 - 6

Climate change New diseases associating with established insect species West Nile Virus.

Mosquito borne disease Disease transmission – summary Disease causing pathogen ingested with blood Multiplies in insect gut Develops in insect gut Migrates into mosquito haemolymph (blood) Transfers to salivary glands Injected into new host 7

1999 West Nile Virus

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Conditions in US perfect for distribution of virus West Nile virus is a flavivirus Conditions in US perfect for distribution of virus a) susceptible birds b) insect vectors present - biting birds and other vertebrates c) susceptible horses/humans 21

WNV in the UK? Level of risk may increase if… Increase in numbers & distribution of human-biting mosquitoes in the UK Introduction of a more efficient mosquito vector WNV in the UK? DoH – surveillance systems for people …… no evidence of WNV infection Local bird population examined ….… positive for WNV antibodies Mosquito surveillance ………… all negative for WNV Overall risk of WNV transmission in the UK categorized by DoH as ‘LOW’.. Level of risk may increase if… Changes in human behaviour, encouraging greater human/vector contact Changes in climate to allow survival of efficient vector

Climate change New invasive species New diseases associated with these.

Aedes albopictus

Aedes albopictus – in USA

Aedes albopictus Importation into California on “Lucky Bamboo” Spread through import and internal movement of used tyres Importation into California on “Lucky Bamboo”

Europe First appearance in Albania in 1979 Since then been reported in: Belgium, Bosnia & Herzegovina Croatia, France, Germany, Greece Italy, Malta, Monaco, Montenegro Netherlands, San Marino, Slovenia Spain, Switzerland, Vatican City

Imported tyres – into UK (According to “Used Tyre Working Group”) 1999: 20,254 tonnes (units 3,116,000) 2000: 34,921 tonnes (units 5,372,462) 2001: 37,473 tonnes (units 5,765,077)

Research: Mosquito breeding in tyre disposal sites in the West Midlands Mosquito breeding potential in disposed tyres in the UK Findings Mosquitoes breeding at all sites Within 1m of vegetation: 60% of tyres sampled housed mosquitoes Within 10m of vegetation, only 3% of tyres had mosquitoes present

Invasive species - UK Mosquito Watch was established in 2005 Environmental health practitioners (EHPs) in responding to pest issues receive insects from public

Invasive species EHPs will likely be one of the first groups to be asked identify new mosquito nuisance-biting species. Need for reporting system that could be related to invasive species.

Invasive species During five years of the scheme, there were 116 confirmed mosquito reports 21 reports associated with other insect groups.

The most commonly reported mosquito species were: Culiseta annulata (56 reports) Culex pipiens (42) Ochlerotatus detritus (7) Aedes/Ochlerotatus sp. (7) Coquillettidia richiardii (1) Anopheles maculipennis s.l. (1)

UK No sign of Aedes albopictus in UK as yet !

Raising awareness - information sheet London Boroughs of Hounslow / Richmond on Thames Thames Water

Climate change Re-emergence of “old” pest species Microclimatic changes.

“Microclimate Change” Bedbugs “Microclimate Change” Household environment

Bedbugs Increase in numbers in recent years Reasons ? Poor hygiene in communal living Increase in overseas travel Freecycle, e-bay Laundry 41

Cimex lectularius – Egg to Adult Bedbug life cycle.   Cimex lectularius – Egg to Adult   Temperature (°C) Complete cycle (weeks) 13 Not completed 15 34 18 22 8 27 4.5

Bedbugs Increase in numbers in recent years Reasons ? Laundry 44

Bedbug control WET/DRY bedding: It is the time time taken to reach the required core temperature of 400C - 500C which is vital Wet bedding, it took about 2.5 times longer to reach the required core temperature.

Climate change Conclusions New diseases associating with established insect species New insect species Re-emergence of “old” pests