|
|
|
|
|
|
  As the District has expanded eastward into the Golden Gate Estates (GGE) area, the mosquito species and larval habitat of concern have changed from salt marsh to fresh water species and production sites. To best target these fresh water species, more information was needed on larval production, so the Research Department started a project to determine where fresh water mosquitoes might be coming from.
A prime, potential larval source in the GGE area is the backyard borrow pit. Many of the homes in GGE are raised on dirt mounds to meet flood requirements. In order to save money, many home owners and contractors dug large pits (borrow pits) in backyards to produce the dirt used for the mounds. This left large pits, frequently filled with organic debris from land clearing and routine yard work, which filled with water when it rained and, on occasion, from a rising water table.
Little is known about the impact these borrow pits have on the production of fresh water mosquitoes. A research program has been instituted to study these borrow pits and their impact on mosquito production.
A total of 30 residential borrow pits covering two distinct areas, one more prone to flooding than the other area, in GGE were selected for study. The pits were visited 3 times per week and data was collected on rainfall, presence or absence of water in the pit and nearby roadside ditches, adult landing rate count, and the presence or absence of different stages of larvae in the pit and roadside ditches. This data has been collected for at least 12 consecutive months so that all seasonal variations in weather and mosquito levels are monitored.
It is hoped that information from this study will allow the District to better understand the impact these borrow pits have on the production of mosquito larvae in the eastern portion of the District.
|
|
|
|
|
