2021 CEQ Annual Report

Invasive Disruptors

Invasive Insects

Climate Change Indicator

The “Invasive Disruptors” described in this section are two examples of species that are not native to Connecticut that have the potential to upset the ecological balance or threaten public health. 
Asian Tiger Mosquitoes58

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Asian Tiger MosquitoThe range of the Asian tiger mosquito is expanding in the United States, particularly into Connecticut and other northeastern states. Infection rates of mosquito-borne diseases, such as Dengue and Zika, are likely to rise over the long term, as a warming climate creates more favorable habitats for mosquitoes. Connecticut is expected to get warmer and wetter over the coming century, enhancing mosquito populations by creating more suitable habitat. Data suggests that precipitation during the summer months has a greater impact on the number of mosquitoes in the state than does winter temperature. Additional information about mosquito management in Connecticut can be found on Department of Energy and Environmental Protection’s (DEEP) website or the Connecticut Agricultural Experiment Station (CAES) portal.ct.gov/CAES.

Technical Note: Collection data for 2016-2018 has been modified from previous reports because of the introduction of new data from a trapping site in Bridgeport.

Emerald Ash Borer59

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   Map of Connecticut showing thr first detection of emerald ash borer. 



The emerald ash borer attacks ash trees almost exclusively. In Connecticut, ash trees make up just slightly less than three percent of the trees in the forest, most of which are white ash. The loss of ash 
trees in a forest stand also reduces vital habitat and allows undesirable invasive plants to fill the gap Emerald Ash Borercreated. Movement of ash, in particular as firewood, nursery stock, logs and wood packaging materials, has been cited as the most likely means by which emerald ash borer has spread so rapidly.60 Additional information about the emerald ash borer in Connecticut can be found on DEEP’s website or CAES portal.ct.gov/CAES.

Technical Note: The “Invasive Disruptors” described in this section are species that are not native to Connecticut that have the potential to upset the ecological balance or threaten public health.  Invasive species have been identified as a cause in decline of at least 48 percent of species listed as threatened or endangered under the United States Endangered Species Act. Information on other invasive species can be found in the Council’s 2022 special report Invasives: Previously Described and Newly Arrived.


58 Connecticut Agricultural Experiment Station (CAES); personal communication from J. Shepard, November 23, 2021.
59CAES, Emerald Ash Borer (Agrilus planipennis); portal.ct.gov/CAES/Publications/Publications/Emerald-Ash-Borer-Agrilus-planipennis.. Image provided by Dr. C. Rutledge, 3-22-2022.
Connecticut’s 2020 Forest Action Plan, December 2020; portal.ct.gov/DEEP/Forestry/CT-Forest-Action-Plan.