rated this year\u2019s bloom<\/a> between 2 and 3, which is mild. Compare that with 2011\u2019s very severe bloom, which peaked between 9 and 10.<\/p>\nNOAA researcher Rick Stumpf says each bloom is different. He and his colleagues use several factors to rate each one.<\/p>\n
\u201cThe mildness is a reflection of how much bloom there is,\u201d he says. \u201cThe amount of biomass, the quantity, and how severe it is over the peak 30 days.\u201d<\/p>\n
Weather is a big factor<\/p>\n
The amount of rainfall in the spring also affects the bloom\u2019s development. Algae feed on phosphorus, a common chemical in farm fertilizer. When farmers apply it to their fields, rain will wash some of it into streams and creeks. That water then flows into the lake through the Maumee River in Ohio.<\/p>\n
![\"A](\"https:\/\/www.newsbeep.com\/us-pa\/wp-content\/uploads\/2025\/12\/LakeErie-e1747670301880-900x507.jpg\")
Algae can grow close to shoreline areas as in this photo of Lake Erie from 2017<\/p>\n
Stumpf says lower-than-average rainfall in 2025 meant less phosphorus for algae to consume, and thus a milder bloom. He also says this year\u2019s growth started later than usual.<\/p>\n
\u201cThe last few years, the bloom\u2019s been pretty well-developed in July,\u201d Stumpf says. \u201cThis year, it wasn\u2019t until well into August when you had the greatest quantity of bloom.\u201d<\/p>\n
Stumpf says one way farmers can limit the amount of phosphorus in the lake is to test their fields for it early.<\/p>\n
\u201cIf you\u2019ve got enough phosphorus in the field, you may not have to fertilize for a couple of years, and that can make a big difference.\u201d<\/p>\n
Navigating the shutdown<\/p>\n
Stumpf says the federal government shutdown in October did affect some of NOAA\u2019s observations. But he says by then, researchers had enough data to rate the bloom accurately.<\/p>\n
\u201cWe do a lot with satellite data, and that data has continued throughout this year\u2019s bloom,\u201d he says.<\/p>\n
That data will also help NOAA figure out what other factors affect harmful algal blooms and how they\u2019ve changed over the last 25 years.<\/p>\n
Size doesn\u2019t always matter<\/p>\n
The size of each bloom doesn\u2019t necessarily reflect how toxic it is. For example, the 2014 bloom was rated moderate to severe (5 out of 10). But it produced enough toxin to contaminate Toledo\u2019s municipal water system that year.<\/p>\n
In general, Stumpf says algal blooms can harm people and animals who are exposed to them. He says the best way to prevent that is to avoid areas of green scum on the surface of the lake.<\/p>\n","protected":false},"excerpt":{"rendered":"This year\u2019s harmful algal bloom in western Lake Erie was among the mildest this century. The National Oceanic…\n","protected":false},"author":2,"featured_media":62488,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[12],"tags":[33569,33570,2960,136,138,137,262,260],"class_list":{"0":"post-62487","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-erie","8":"tag-algae","9":"tag-algal-blooms","10":"tag-environmental-health","11":"tag-erie","12":"tag-erie-headlines","13":"tag-erie-news","14":"tag-great-lakes","15":"tag-lake-erie"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us-pa\/wp-json\/wp\/v2\/posts\/62487","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us-pa\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us-pa\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-pa\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-pa\/wp-json\/wp\/v2\/comments?post=62487"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us-pa\/wp-json\/wp\/v2\/posts\/62487\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-pa\/wp-json\/wp\/v2\/media\/62488"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us-pa\/wp-json\/wp\/v2\/media?parent=62487"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-pa\/wp-json\/wp\/v2\/categories?post=62487"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-pa\/wp-json\/wp\/v2\/tags?post=62487"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}