Most likely, when you hear the term \u201crenewable energy,\u201d you\u2019d picture solar energy or wind power installations rather than enormous underwater turbines.<\/p>\n
However, engineers are tying these machines to the ocean floor along some North American and U.S. coastlines in order to harness renewable tidal power.<\/p>\n
It seems like an almost imperceptible, dependable, and clean system. However, scientists are observing something concerning in their impact on underwater ecosystems.<\/p>\n
When someone thinks about putting a wind turbine underwater<\/p>\n
You would not be wrong if you pictured big devices under the\u2002sea when someone said \u201ctidal turbines.\u201d<\/p>\n
A more recent innovation in clean energy, tidal turbines have been in the works for decades as engineers have\u2002sought to capitalize on the ocean s natural movements.<\/p>\n
Like underwater windmills, they generate electricity from turning blades that are\u2002driven by the sea\u2019s current.<\/p>\n
But don\u2019t feel like you\u2019ll be making use of some ancient tech; tidal turbines have yet to realize their potential as a source\u2002of renewable power.<\/p>\n
They don\u2019t just produce energy. They can modify their environment<\/p>\n
Offshore wind farms have been linked to altered migration routes and increased mortality in bird life.<\/p>\n
Underwater tidal turbines bring a similar twist to the marine world. These machines don\u2019t just produce energy \u2014 they change how the ocean environment behaves.<\/p>\n
Because tidal turbines sit smack in the middle of currents and migration routes, they can cause changes in water flow and acoustics, and influence behavior patterns that fish have used for millennia.<\/p>\n
That\u2019s why people refer to the routes fish form as \u201csuperhighways\u201d \u2014 continuous pathways they start using around and through the turbine installations instead of their traditional corridors.<\/p>\n
But here\u2019s the worrying part: scientists still don\u2019t fully understand where those fish are going along these new routes, or how these behavioral shifts could ripple across entire ecosystems. That uncertainty is exactly what has experts raising red flags about the use of underwater turbines<\/a>, and it\u2019s important to understand how much damage is being done.<\/p>\n Fish have started building \u201csuper highways\u201d. Now we know where they lead to<\/p>\n This is where the tidal energy story gets unexpectedly biological.<\/p>\n Ocean currents and tidal flows don\u2019t just push water. They shape where fish go. Around powerful tidal sites like Canada\u2019s Bay of Fundy, researchers have observed patterns in fish movement that almost resemble highways \u2014 consistent routes that fish follow as they migrate along the currents.<\/p>\n Studies in the Bay of Fundy, especially around areas where tidal turbines are being tested, have shown that big migratory species \u2014 including shad, salmon, herring, and striped bass \u2014 travel long distances through the macrotidal channels year after year. This is one of the conclusions from Natural Resources Canada<\/a>, a government\u2019s agency.<\/p>\n Scientists use tagging and tracking to map these movements and are starting to treat them like migratory superhighways through the tidal system.<\/p>\n What\u2019s fascinating \u2014 and concerning \u2014 is that these routes intersect with where tidal energy devices are being deployed<\/a>.<\/p>\n From Canada to New Zealand: But it\u2019s not the same highway<\/p>\n Half a world away in New Zealand\u2019s Cook Strait, another tidal hotspot, scientists are also mapping how strong, complex tidal flows influence marine life patterns.<\/p>\n Although specific \u201csuperhighways\u201d haven\u2019t been formally labeled yet, Cook Strait\u2019s powerful bi-directional tidal currents drive migration and movement for a wide range of marine species, from schooling fish to cetaceans, underscoring how currents alone can shape travel routes through what looks like open ocean.<\/p>\n So now it\u2019s not just turbines and energy potential we need to think about.<\/p>\n