July Mosquito & Tick Report — Long Island
July is peak mosquito season on Long Island. High heat, humidity, and frequent afternoon thunderstorms create near-ideal breeding conditions. Mosquito populations reach seasonal maximums during the third and fourth weeks. Tick activity remains elevated with adult deer ticks and lone star ticks active across both counties.
July Activity Summary
🦟 Mosquito Activity
Very High
🕷️ Tick Activity
High
Suffolk County Rainfall
3.5–4.6 inches typical for July (Suffolk County)
Nassau County Rainfall
3.3–4.2 inches typical for July (Nassau County)
🦟 Mosquito Activity — July
July represents the highest mosquito pressure of the year for most Long Island communities. Culex pipiens populations reach peak density, particularly near standing water, retention areas, and South Shore marshes. Asian tiger mosquito activity is intense in suburban yards. The 7–10 days following any significant rainfall event see the sharpest population spikes.
🕷️ Tick Activity — July
Deer tick nymph activity begins to decline in late July as adults emerge. Adult blacklegged tick activity is highest in wooded and edge habitat — properties backing to woods, parks, or trails remain high-risk. Lone star tick adults are most active in July, particularly in Riverhead, Southampton, and eastern Suffolk County.
Active Species This Month
Culex pipiens (Northern House Mosquito)
Peak season. Most active from dusk to dawn. West Nile Virus risk highest in July–August.
Aedes albopictus (Asian Tiger Mosquito)
Peak daytime activity in shaded suburban yards. Aggressive biter.
Coquillettidia perturbans (Cattail Mosquito)
Peak South Shore saltmarsh emergence.
Ixodes scapularis (Deer Tick)
Adults emerging as nymph season winds down.
Amblyomma americanum (Lone Star Tick)
Peak adult activity across eastern Suffolk County.
Towns Seeing Elevated Activity in July
July Prevention Recommendations
- Schedule mosquito barrier treatments every 3 weeks through the height of summer
- Drain any standing water within 24 hours of rain events
- Avoid outdoor activity between dusk and dawn when mosquitoes are most active
- Use oscillating fans on patios — mosquitoes are weak fliers and avoid air movement
- Treat ornamental ponds with Bacillus thuringiensis israelensis (Bti) dunks
- Keep grass cut below 4 inches to eliminate resting habitat
- Wear long sleeves and pants for tick prevention during outdoor activities
Looking Ahead
August typically sees continued high mosquito activity through mid-month before beginning a gradual seasonal decline. Late-summer heat waves can extend peak conditions well into August. Tick activity remains consistent through September.
This report contains seasonal activity estimates based on historical Long Island mosquito and tick patterns, typical weather conditions, and regional environmental factors. It is not a government health advisory, live surveillance data, or a guarantee of specific conditions. For public health information about mosquito-borne illness in New York State, visit the NYS Department of Health website.