YORK, Va. (WAVY) — Following our recent heavy rain and hot stretch of weather, algae blooms have been spotted in area rivers.

In photos and video captured by Savannah Mapes – who is researching blooms like this one at the VA Institute of Marine Sciences on the Middle Peninsula – you can see the algae blooms along the York River.

Margalefidinium polykrikoides in the York River. Picture from Savannah Mapes.

In the pictures, the dark areas are spots where Margalefidinium polykrikoides has been spotted. Nicknamed Marg by the scientists at VIMS, this algae is found in coastal waters worldwide and has bloomed almost annually for the past several decades in the York River area.

Dr. Kimberly S. Reece at VIMS tell me these algae blooms occur most often in the late summer, and can be impacted by many factors including temperature, recent rainfall, and salinity.

In more recent years, blooms have been noted in the lower Chesapeake Bay’s main stem and in the James, Elizabeth and Lafayette Rivers.

The blooms can impact marine life, including oysters in the river – but the human impact is usually minimal. Some respiratory issues have been reported over the years. If you have a reaction to call the HAB Hotline. The HAB hotline at 1-888-238-615 with any questions about human health.

To report a bloom, people can go to the VDH site and fill in a HAB online report form.

For more on Marg blooms, visit the VIMS website.