HAB Info

What are Harmful Algal Blooms (HABs)?

Most algae are harmless and are an important part of the food web. Algae are naturally present in slow moving streams, lakes, marine waters and ponds in low numbers. Certain types can become abundant and form blooms under the right conditions. Some algae can produce toxins that can be harmful to people and animals. These are collectively called harmful algal blooms (HABs).

Algae blooms most frequently occur in nutrient-rich waters, particularly during hot, calm weather.

Because it is hard to tell a harmful algae bloom from other algae blooms, we recommend avoiding contact with any floating rafts, scums, and discolored water. Find out what water bodies have a blue-green algal bloom notice.


Freshwater Blue-green Algal Blooms

Blue-green algae, technically known as cyanobacteria, are naturally present in lakes and streams in low numbers. Blue-green algae can form HABs that discolor the water or produce floating rafts or scums on the surface of the water. These can cause health risks to people and animals when they are exposed to them.

Blue-green algae blooms can occur in freshwater lakes and ponds and can reduce the recreational value of a water body, due to unpleasant appearances and odors, and can cause a variety of ecological problems, such as reduced oxygen levels. They also have the potential to form harmful (toxic) blue-green algal blooms, although the factors that cause blue-green algae to produce toxins are not well understood.

Harmful blue-green algae blooms can cause health effects when people and animals come in contact with them. Symptoms can include nausea, vomiting, diarrhea, skin or throat irritation, allergic reactions or breathing difficulties. Blue-green algae can also produce toxins that affect the liver and nervous systems when water is consumed in sufficient quantities.

What should you do if you see a Harmful Algal Bloom?

If you suspect that you are observing a HAB, you should report your observation.  Reports can be directed to either the CLA or to NYSDEC.  Information that you report needs to include:

  • (a) the date and time of the observation;
  • (b) an exact description of the bloom’s location;
  • (c) the size of the bloom in relation the that area of the lake in general [small, widespread, at shoreline only];
  • (c) a description of the bloom [color, texture, density, if scum is present];
  • your name and contact information. 
  • NYSDEC will request a photo if possible.  The CLA also will appreciate receiving an emailed picture of the bloom.  NYSDEC can be reached via the HABs Notifications link that is provided below.  The CLA can be reached by telephone (716-763-8602) or by email (info@chautauqualakeassociation.org).
  • NYS recommends that contact with all blooms, surface scums, and visibly discolored water should be avoided.  Know it, Avoid it, Report it.  Just because there is a bloom at one location of the lake does not mean that the whole lake is in a bloom condition.  Chautauqua Lake is a large lake.  If you come upon a bloom, explore the lake further for recreational opportunity and you will likely find areas that do not possess blooms.

More about Harmful Algal Blooms (HABs):

  • The Chautauqua Lake Association is the only entity that NYSDEC collaborates with locally on identifying and confirming the presence of HABs.  Persons suspecting the presence of HABs should report such as detailed above.  Reports received at the CLA office will likely be field investigated by CLA staff.  Depending upon the severity of the bloom, a sample may be collected which will then be sent off to a lab for analysis.  Due to its limited budget, the CLA is not able to sample all suspected blooms. The CLA collaborates with NYSDEC, SUNY ESF and the NYS Federation of Lakes Association on HAB matters in addition to informing local officials of bloom identification results.NYSDEC manages a NYHABS Program that includes a state-wide map of HAB locations.  The map is active from May through October annually and can be accessed via NYSDEC’s HAB Webpage (http://www.dec.ny.gov/chemical/93310.hyml) or directly via http://on.ny.gov/nyhabs.  HABs info can be viewed in different modes on the site.  The site is only as comprehensive as the reports that are filed.  Thus, it is important that all bloom sightings be reported.  Blooms that the CLA confirms to exist are shown on the map.If you experience any adverse effects from a possible HAB that would require a doctor’s visit for either a human or a pet, ask the doctor or vet to report his/her findings to the Chautauqua County Health Department.


Below are some helpful resources for staying informed and safe around HABs:


Harmful Algal Blooms (HABs) Photo Gallery 

Harmful Algal Blooms (HABs) Notifications Page
Map and table of waterbodies that have a HABs.

Harmful Algal Blooms (HABs) Archive Page 
Archived reports of waterbodies that had a HAB.

Harmful Algal Blooms (HABs) Additional Information
General information about HABs DEC programs related to HABs and water quality.

Harmful Algal Blooms (HABs) DEC Brochure 
Created by the NYS DEC.

Effects of Eating Fish near Harmful Algal Bloombs (HABs)