Harmful Algal Bloom Monthly Report - August 2023

**Specifics on some ponds: **
Of the blooms we have seen this summer, Miacomet Pond has been blooming for the longest at 11 weeks (Since early June). Sesachacha Pond has had a bloom for 7 weeks (since early July). Reporting seems to be similar between this year and last year but is up since 2021 and 2020. 

**Causes of blooms: **
We can't say for sure why we are seeing more blooms than in previous years. Harmful algal blooms are caused by an excess of nutrients, like nitrogen and phosphorous, entering a water body and providing a constant food source for many species of algae. Sources of these nutrients common to Nantucket include fertilizer (gardens, lawns, farms), animal waste (waterfowl or pets), and stormwater runoff from nearby roads. Increases in fertilizer use around ponds, or large rainstorms can certainly exacerbate the problem. Any organism provided with an excess of food, enough to skyrocket the local population, can alter local food chains. In this case it is microscopic algae feeding on excess nutrients and exploding in population in a small area.

**Water Temperature Summer 2023: **
The average temperature of the ponds this summer have been around 68 degrees (Fahrenheit) in June, 77 degrees in July, and 78 in August.

**Takeaways: **
Algal blooms are going to be here in the summer for the time being. Changes in fertilizer use, and larger pond management projects are ways that we can hopefully curb the number that we are seeing. If a member of the community would like to report a bloom they can do so using the QR code present on the harmful algal bloom signs. Posted at all of the monitored ponds.  The red and yellow algal bloom signs at the ponds are there for everyone's safety. Always use caution when recreating in ponds where a bloom may be present. I am happy to be a resource for anyone who has questions or concerns about algal blooms.