BIOLOGICAL CONTROL OF MOSQUITOS SHANE MURPHY, NOAH PERLUT, AND CHRISTOPHER WATT

DEPARTMENT OF ENVIRONMENTAL STUDIES. UNIVERSITY OF NEW ENGLAND. BIDDEFORD MAINE

Abstract Mosquitoes are known vectors of diseases such as West Nile Virus and Eastern Equine Encephalitis (HHH). In an effort to reduce human exposure to these diseases, the University of New England’s Environmental Health and Safety Department has teamed up with Facilities and the Department of Environmental Studies to create a biologically friendly method of mosquito control. In order to avoid the environmental impact of biocides, we undertook a non-toxic, biological approach to mosquito control. By putting up twenty-four bird and twemty-five bat boxes on campus, the university hopes these will attract the natural predators of the mosquito. We strategically established this infrastructure in areas around campus to which mosquitoes are most abundant and where the UNE community congregates. Twenty-five planters, containing plant species that have been known to repel mosquitos, such as Pelargonium graveolens, Citrosa, Lavandula, and Ocimum basilicum, have also been placed around campus, specifically near doorways and walkways of high human traffic. This program has been in application for two years now and was a great success with fledging 45 birds in the summer of 2014 and even showed superficial bat use. This program will continue in the future, aiming to further reduce possible exposure to mosquito-borne diseases.

Introduction The University of New England is in close proximity to wetlands and shaded forests, which can become the breeding grounds for numerous species of mosquitos. This could pose a health threat to students and faculty on campus, as a result of exposure to mosquito borne illnesses. The mosquito project is designed to have two types of biological control: passive integrated plant management (IPM) and actively encouraging animals that regularly include mosquitos in their diet. The use of IPM plants was intended to provide widespread and nontoxic chemical control. In a paper by Martin Jacobson, Mexican Marigold, Tapetes minuta, was explained to repel larva of the yellow fever mosquito, Aedes aegypti, via the compound (E)-5-ocimenone (Jacobson, 1982). Several varieties of plants were found in these set-ups such as Bee Balm, Mint, Citronella, Marigold, Basil, Rosemary and Lavender. The project also utilized 25 bird and 24 bat boxes, in the hopes of encouraging bird and bat species that regularly consume mosquitos. This aspect of the project focused on Eastern Bluebirds, Tree Swallows, and Little Brown Bats. The Mosquito Project had a diverse array of goals that complements the diverse approaches to mosquito management. Naturally, the primary goal was to diminish the mosquito population on campus and the subsequent amount of complaints received.

Methods

This study took place during the months of May-August 2014. A total of 25 bird and 24 bat boxes were set up in areas near wetlands and wet forests on the University of New England's Biddeford Campus. Bird and bat boxes were strategically placed in order to attack the source of the mosquito population. Observations were taken five times a week in order to see what species were using each box. All bird species, adults and chicks alike, were banded by taking the bird from the box or the use of mist nets. Bat species were only recorded as an observation. Integrated pest management plants were set up set up to contain four different species surrounding a cherry tomato plant. A majority of the plants were planted in tubs and put in front of buildings, while a few were planted in soil beds near sidewalks. These tubs and plants were watered four days per week.

References•Brooks R.T., Biodiversity and Conservation, Declines in summer bat activity in central New England 4 years following the initial detection of white-nose syndrome, 2011, Volume 20, Number 11, Page 2537, Accessed 4/29/14,http://link.springer.com/article/10.1007%2Fs10531-011-9996-0•Jacobson M, Economic Botany, Plants, Insects, and Man- Their Interrelationships, 1982, Volume 36, Number 3, Accessed 10/11/2014, http://www.jstor.org/discover/10.2307/425440

 Acknowledgements • Ronnie Souza, the head of the environmental health and safety department, Phil

Tachereau, University of New England's Master Gardener

Table 1. Bird species egg, chick and fledgling counts including the overall success rate from egg to fledgling.

Results and Discussion Into its second summer, the Mosquito Project is still in the stages of working to establish quantitative ways that will outline the projects effectiveness. The success of this primary objective was largely attributable to the early deployments of the bird and bat boxes and the IPM plants, as compared to the pilot year, in which their deployment was delayed.

The Mosquito Project was successful in many secondary goals as well, namely the increase in nesting activity of target bird species on campus. Nineteen pairs of birds nested for the course of the summer and 11 successful nests. Four of the female birds were recaptures from the first year of the project. This increases the likelihood that both they and their chicks will return here next summer.

The part of the Mosquito Project that wanted to attract bats to campus did not share the success its counterpart components have. While a number of factors are responsible, including the delay between the boxes becoming a regular feature of the UNE landscape and the bat’s realization of their existence, but also due to an invasive European fungus, Geomyces destructans, that has decimated the population of little brown bats in New England. In central Massachusetts, a 72% reduction in bats was found around the Quabbin Reservoir since 2010 (Brooks, 2011). When colonies are infected the mortality rate can be anywhere from 30% to 99% (Johnson L, et. al pg. 1); the bats have no immunity to this novel pathogen. As a species that eats nearly their weight in insects every night, part of that as mosquitos, their loss is a huge blow to mosquito control.

Overall, the project has replaced the need to spray harmful chemicals to eliminate mosquitoes. This program has shown that alternate methods can be just as effective in controlling mosquitoes as those traditionally used. The University of New England’s Mosquito Control program sets a great example of how mosquito control should be done.

Figure 1. Bird and bat boxes near the UNE’s event tent and kiosk. Red represent bird boxes,yellow represents bat boxes and green represents mosquito repellent plant tubs.

Figure 2. Bird and bat boxes surrounding the Barbara Hazard Fields. Red represent bird boxes,yellow represents bat boxes and green represents mosquito repellent plant tubs.

Figure 3. Bird and bat boxes located around the Sokokis pond and along the forests edge. Red represents bird boxes, yellow represents bat boxes and green represents mosquito repellent plant tubs.

SpeciesNumber of Nests

Number of Eggs

Number of Chicks

Number of Fledglings

Success Rate(%)

Eastern Bluebird (Sialia sialis) 10 46 33 24 52.17

Tree Swallow (Tachycineta bicolor) 5 10 10 10 100.00

Black-capped Chickadee (Poecile atricapillus) 4 17 11 11 64.71

Common Name Scientific NameBasil Ocimum basilicumBee Balm MonardaCitronella Pelargonium citrosumLavender LavandulaMarigold TagetesMint MenthaRosemary Rosmarinus officinalis

Table 2. Mosquito repellent plant species used in this study.