Why Do Fish Travel in Schools?

Nature 3 Minutes

From Scubadiving.com:

I am completely enclosed, suspended in a sphere of clear warm water smaller than my office. I am not surrounded by bricks and mortar, but living walls made of thousands of silvery bodies. The schooling silversides are so thick that I can’t see the surrounding coral canyon they’ve filled on this Cayman reef. As swiftly as I was engulfed, I am spat back into the bright blue world as the fish sweep past me to escape a marauding tarpon.

Shoals and schools of fish are similar, but there are differences. A shoal is any gathering of fish (single or mixed species), something about 50 percent of all fish species does at some point. Strictly, schools are much tighter formations, where the fish are fully synchronized, usually dominated by a single species of a similar size. Many schooling fish are silvery, which keeps them safe, not only because those scales reflect the water, making them harder to see, but they also dazzle and confuse predators. To us, these defensive maneuvers are an enchanting spectacle; the fish dance as if they are a single, giant creature.

As effortlessly balletic as it looks, these coordinated and unrehearsed mass twists and turns are challenging. It is not something a group of people could do. It used to be thought that fish’s unique lateral line sense, which allows them to feel vibrations in water, was the main control. But recent studies show that vision is the dominant sense in synchronized schools. Fish that school typically have eyes mounted on the sides of their head; the exact spacing of individuals, and the precise and unified movement are controlled mainly by eye contact.

Many schools form for defense. The main protective advantages of safety in numbers are: Each member of the school has less chance of being eaten since predators struggle to pick out an individual, and when faced with a predator, most individuals can take evasive action before it gets close, based on the movements of the other fish. The closer the fish pack together and the more unified their movements, the safer they are, which has driven the evolution of this complex behavior.

Not all gatherings are for protection. Fish also form shoals to feed, migrate, rest, court and spawn. Some herbivorous species of damselfish live alone and aggressively defend the gardens where they farm algae—even against divers. Other species can’t raid these gardens alone, but many species of surgeonfish, parrotfish and rabbitfish will shoal to use the weight of numbers to gain access.

Many nocturnally active species, like snappers, grunts, sweetlips and bigeyes, are commonly seen resting in mixed groups during the day. These shoaling fish are often horizontally striped, a pattern thought to signal peaceful cooperation in the fish world. (Vertical bars are often associated with aggression and territoriality.)

Smaller reef fish tend to spawn regularly, but larger species reproduce less frequently, often gathering in large numbers just a few times each year to spawn. Large, solitary reef predators like Nassau groupers and bohar snappers are classic examples of species that gather impressively for spawning events. Sadly, this is a sight that is vanishing from the oceans, because these gatherings make it easy for people to net large numbers of fish, often wiping out the entire adult population of a species from a reef system in one fell swoop.

As photographers, our best shots will emphasize the togetherness of the fish. We want tight formations of neat, repeated shapes to make our pictures pop. However, the one thing guaranteed to mess up pleasing arrangements is getting too close! Shooting schools requires that we unlearn the golden rule of underwater photography and keep a bit of distance (in relative terms, anyway) to maintain those fantastic formations in our photos. What benefits the fish is also good for our photos.

SOURCE: SCUBDIVING.COM

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Published by pat frederick

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76 thoughts on “Why Do Fish Travel in Schools?”

  1. Morning All!
    dark and gloomy out there. the deck is wet and there’s a light rain falling.
    my granddaughter bought a car last night–she was so excited. And yes, SHE’S been working summers and weekends when she could to save money. Plus she saved a lot of birthday and Christmas money to pay for this. She has her permit and goes for her license soon, but they found this deal on facebook marketplace. the guy is local and my SIL knows him. so right time, right place. She’s over the moon right now.

    Liked by 1 person

        1. Could be! Whenever he doesn’t show up, I remember that he was gone for almost a year before, then re-appeared so I’m not worried yet.

          Liked by 1 person

  4. Eric Daugherty
    @EricLDaugh
    🚨 BREAKING: A judge has blocked South Carolina from allowing Assistant AG Harmeet Dhillon to cleanse the state voter rolls of all illegal aliens.

    Millions of voter data are now being withheld from the DOJ – but Harmeet Dhillon vows the rolls WILL be cleaned.

    “I will allow nothing to stand in the way of our mandate to maintain clean voter rolls.”

    “Guess who issues the SSNs? The federal government! The idea they are secret from the DOJ is silly at best.”

    “One CITIZEN, One Vote.”

    Liked by 1 person

  7. never invite the snake in…

    sync
    September 6, 2025 7:55 am

    Who needs Mamdani…they got Adams

    New York City Mayor Eric Adams has implemented significant changes regarding the Islamic call to prayer and Muslim holidays. Mosques and masjids in NYC are now allowed to broadcast the Adhan (call to prayer) publicly without a permit every Friday and during Ramadan, as long as they adhere to reasonable noise levels and other guidelines. Additionally, just before 9/11 anniversary, in 2025, Mayor Adams elevated Muhammad’s birthday to “holiday” status in NYC.

    Liked by 1 person

  8. woman registered her dog to vote and voted for her.
    FTA
    A 62-year-old California woman was charged Friday with five felonies for illegally registering her dog to vote and casting ballots in her dog’s name in the 2021 state gubernatorial recall election and the 2022 primary election, according to the Orange County District Attorney’s office.

    California’s elections were significantly changed in 2021 after Democrat California Gov. Gavin Newsom signed Assembly Bill 37, making universal mail-in voting permanent and requiring counties to automatically mail ballots to all active, registered voters. According to a press release from the Orange County’s DA office, 62-year-old Laura Lee Yourex of Costa Mesa has been charged with one felony count of perjury, one felony count of procuring or offering a false or forged document to be filed, two felony counts of casting a ballot when not entitled to vote, and one felony count of registering a non-existent person to vote.

    In October 2024, the DA’s office was contacted by the Orange County Registrar of Voters’ Office after a resident allegedly self-reported that she registered her dog to vote. The resident claimed that she cast a mail-in ballot addressed to her dog, Maya, for the 2021 gubernatorial recall election and the 2022 primary election.

    “The dog’s vote was successfully counted in the 2021 gubernatorial recall election but was rejected in the 2022 primary,” the press release states.

    Per the California Elections Code, in order to register to vote in the state, a voter would need to fill out and submit an Affidavit of Registration, which includes the voter’s name, residence, mailing address, date of birth, political party preference and a certification that the voter is a citizen of the United States.

    With proof of residence not required when dropping off or casting a ballot during an election, it is required when first registering.

    “As a result, the 2022 primary ballot cast in Maya Jean’s name was challenged and rejected,” the press release states. “The 2021 election to recall California Governor Gavin Newsom was voted down by 61.9% of voters.”

    Upon the Orange County District Attorney’s Office Bureau of Investigation looking into the case, officials found “sufficient evidence” to file criminal charges against Yourex.

    According to the press release, Yourex allegedly posted on her social media a picture of her dog in January 2022 “wearing an ‘I voted’ sticker and posing with her ballot.” An additional photo was allegedly posted on Yourex’s social media in October 2024, showing her dog’s tag and a vote-by-mail ballot with the caption, “maya is still getting her ballot,” despite the dog having previously passed away.

    Yourex is scheduled to be arraigned Sept. 9 and faces a maximum sentence of six years in state prison if convicted on all counts.

    https://thelibertydaily.com/california-woman-illegally-registers-dog-casts-mail-ballots/

    Liked by 1 person

  12. Just The News: “As the U.S. gets most of its pharmaceutical ingredients from China and India, the Trump administration has been taking steps to bring back pharmaceutical manufacturing to the U.S. in order to break the U.S.’ dependency on foreign countries. 

    Health and Human Services Deputy Assistant Secretary for Preparedness and Response John Knox said last month that 70% of active pharmaceutical ingredients (APIs) and key materials are manufactured in China and India. He also said that about 90% of antibiotics are manufactured in China. 

    Innovative solutions to the insecure supply chain

    “Just the News, No Noise” host John Solomon asked Knox on Friday about potential innovative solutions where generic drugs can be produced in something like a one-room factory in the U.S. “I think that’s really crucial when we look at onshoring medications,” Knox said on the TV show. “We here in the United States have a completely different labor force than what they do in China and India.”

    Knox explained that “We don’t have slave labor here and competing at those levels with huge bulk factories..we don’t have the capacity or the ability to do that. So we have to look at new and innovative ways like you mentioned, on how to strategically come up with ways to make things simpler and faster.”

    He said that there are a lot of benefits to the private and public sector working together on a matter like this. “We can do 3D printing of medications and pill form we have,” Knox said. “We’re working on projects where we don’t have to have the key starting materials. It completely bypasses that to make the active pharmaceutical ingredient. So we’re looking at ways of how we can jump ahead of the curve using technology.”

    Last month, President Donald Trump signed an executive order to fill up the Strategic Active Pharmaceutical Ingredients Reserve (SAPIR) with critical drug components in order to ensure a secure domestic supply chain for critical medications. 

    “Restoring capacity for domestic production of essential pharmaceutical products is essential to safeguarding national health and security against global supply chain disruptions,” the White House said in a statement. 

    Rep. Miller-Meeks: Tax incentives, re-evaluate the FTC and the U.S. supply chain

    There are also incentives in the recently passed “one big beautiful bill” that created tax incentives to get the process rolling for having APIs made in the U.S. Rep. Mariannette Miller-Meeks, R-Calif., said on the “Just the News, No Noise” TV show that it is also important to evaluate the Federal Trade Commission and their role in drug manufacturing in the U.S.

    “We have to make sure that the FTC does its job, and when there’s too much vertical integration, it ends competition,” she said. “That’s where the FTC needs to step in. When you have consolidation in a marketplace, you don’t have competition that helps bring down costs.”

    Miller-Meeks said that the entire supply chain also has to be evaluated to ensure Americans get pharmaceutical drugs at a good price. 

    “Thirdly is the work that we’re doing on pharmacy benefit managers and looking at the entire supply chain, looking at this opaque middleman and helping to bring supply costs down,” she said. “But it also helps support the pharmaceutical industry, including generic pharmaceuticals.”

    Liked by 1 person

  13. Just The News: “President Donald Trump announced Friday night that he would be sending National Guard troops to New Orleans and pledged the city would be “safe” within two weeks.

    The announcement follows Trump mobilized the Guard in Washington, D.C., last month to help reduce the district’s crime. Trump first floated sending troops to New Orleans on Wednesday after Louisiana’s Republican Gov. Jeff Landry asked the president for help, The Hill reported.

    Trump did not state exactly when the troops would be sent to the southern city but confirmed plans to federalize its law enforcement in a similar manner to his administration’s take over of Washington’s Metropolitan Police Department.

    “We’re going to come into New Orleans, and we’re going to make that place so safe,” Trump said during an event in the White House’s newly renovated Rose Garden. “It’s got a little problem right now, a couple of headaches, like murders, a lot of little murders going on, and we’re not going to stand for it. And we’re going to come in, we’re going to clean it up.”

    Trump previously indicated he would send troops to Chicago next, but the state’s Democratic governor and the city’s Democratic mayor have both protested federal involvement. 

    The president said he is going to make New Orleans the “safest place” and then send troops to other cities with crime problems. Trump has threatened to send troops to Baltimore if Maryland’s governor is not able to reduce crime. 

    “[New Orleans’] going to be the safest place, just like this is the safest place,” Trump said. “And then we’ll be going elsewhere throughout the country, we’re going to bring crime down, because we can’t have cities that are unsafe.”

    Liked by 1 person

  14. Just The News: “President Donald Trump signed an executive order Friday that creates a “state sponsor of wrongful detention” designation for countries that illegally detain Americans. The order comes the same day that Trump added “Department of War” as a secondary title for the Department of Defense in an attempt to rebrand the United States military. 

    The state sponsor order gives Secretary of State Marco Rubio the authority to punish countries he deems a sponsor of “wrongful detention.”  Punishments include sanctioning countries and blocking nationals from those countries from entering the United States. 

    “The United States must strengthen efforts to protect U.S. nationals from wrongful detention abroad,” Trump wrote in the order. “The United States Government is committed to using every tool available to curb this coercive tactic used by foreign adversaries and must hold such adversaries to account. 

    “No American should fear being taken as a political pawn by rogue states,” the order continued. “Wrongful detentions are an affront to the rule of law and aim to undermine our leadership on the world stage. The United States will not tolerate these attacks on our sovereignty and U.S. nationals.”

    The order also gives Rubio the authority to terminate the designation if countries return the detained Americans, make changes to policies regarding wrongful detention and prove they won’t illegally detain Americans again.

    “[The president’s] new Executive Order delivers unprecedented action to protect Americans from wrongful detention abroad,” Rubio said in a post on X. “Designating State Sponsors of Wrongful Detention sends a clear message: If you attempt to use an American as a bargaining chip, you will face severe consequences.”

    Trump has secured the release of 72 detained Americans in his second term so far, including Marc Fogel and Paul Whelan who were wrongfully detained in Russia.”

    Liked by 1 person

  15. Just The News: “President Donald Trump on Friday told reporters that he plans to host the 2026 G20 summit at his resort and golf course in Doral, Florida. Trump initially planned to a hold a G7 summit at his resort in 2020 but dropped the idea after he faced backlash over ethical concerns about hosting a global summit at one of his own properties.

    The White House told CBS News that the resort will host the economic summit “at-cost, and will receive no profit from either the State Department or a foreign government.” 

    A Trump administration official also told the outlet that the guest list for the 2026 summit is expected to be smaller than previous years and the U.S. “will be taking a back-to-basics approach to its host year, streamlining the summit and related workstreams and aligning the agenda with the G20’s founding goals of economic growth and financial stability.”

    National Economic Council Director Kevin Hassett will serve as the point person for the summit, which is scheduled to take place Dec. 14-15, 2026.”

    Liked by 1 person

  16. “Dearborn Heights’ Arabic Police Patch Snafu Is A Badge Of Surrender”

    The Federalist, By: Brianna Lyman, September 05, 2025

    Dearborn Heights police department

    ENTIRE ARTICLE: “Dearborn Heights, Michigan, Mayor Bill Bazzi announced Friday that the new Arabic police patch was not “official” — but didn’t rule out adopting such a badge of surrender in the future.

    A Facebook post from the police department posted earlier this week read: “The Dearborn Heights Police Department [DHPD] is proud to share a new optional patch that our officers may wear as part of their uniform,” accordin to Fox News.

    The patch, according to the post (which appears to have since been removed), “incorporat[ed] Arabic script alongside English” and was “designed … to reflect and honor the diversity of our community – especially the many residents of Arabic descent who call Dearborn Heights home,” Fox reported. It purportedly “represent[ed] unity, respect, and our shared commitment to service.”

    Bazzi announced Friday on the DHPD Facebook page that the “patch effort” was an internal discussion “among some” within the department, but “was not put forth for consensus or further review.”

    “Should efforts like this be formally undertaken to make any changes to the Police uniform, it is our goal to include multiple PD stakeholders for a larger conversation, to ensure all are included in the discussion,” Bazzi said in a statement.

    But “efforts like this” should never be formally undertaken. The hallmark of assimilation is learning and embracing the language — which in this country, is English. The fact that city officials even considered the badge might be necessary only underscores what’s becoming increasingly obvious to everyone in America: Too many immigrants have no interest in assimilating. It’s a dangerous reality, one the founders understood all too well.

    George Washington noted in a 1794 letter that when immigrants settled in a “body,” they “retain the language, habits & principles (good or bad) which they bring with them; whereas, by an intermixture with our people, they, or their descendants, get assimilated to our customs, manners and laws: in a word, soon become one people.”

    “Dearborn Heights’ Middle Eastern or North African population was 39% as of 2023,” Fox 2 Detroit reported. The neighboring city of Dearborn “became the first Arab-majority city in the United States” in the same year, as previously noted in The Federalist.

    Washington understood that allowing immigrants to form ethnic-enclaves discourages assimilation and prevents the nation from being “one people.”

    Similarly, Benjamin Franklin, watching the mass influx of Germans into Pennsylvania, feared that Pennsylvania “will in a few Years become a German Colony. Instead of their Learning our Language, we must learn theirs, or live as in a foreign country.” Franklin’s comments underscore the concern that when migrants arrive in masses, they don’t assimilate — they instead retain their language and culture. They form mini colonies that leave their customs intact, leaving the host society to adjust around them, rather than the other way around — just like what’s happening in Dearborn and Dearborn Heights.

    Washington and Franklin’s comments only underscore why Dearborn Heights’ Arabic patch snafu is not a symbol of “unity” but a symbol of disunity. Whether such a patch would be “optional” or not, there is no practical reason for any city to adopt or promote police badges in foreign languages or for police officers in an American city to wear Arabic script — unless it’s to accommodate a community that won’t assimilate.

    Our republic was never supposed to work this way. As Alexander Hamilton warned in 1802, “The safety of a republic depends essentially on the energy of a common National sentiment; on a uniformity of principles and habits; on the exemption of the citizens from foreign bias, and prejudice.”

    Pandering to unassimilated ethnic-religious enclaves means we’ve replaced assimilation for appeasement.”

    Liked by 1 person

  23. Well, I just got back from buying a new weed eater. The battery for my oldest B&D weed eater would only take a weak charge, not enough to do any good at all. Since it’s impossible to get new batteries, I bit the bullet and bought a DeWalt weed eater. It is charging now and my not-quite-so-old B&D weed eater w/the lithium battery is almost charged up again as well. I did most of the exterior of the east fence line with it earlier. Things just don’t last any more!!!

    Just The News: “The Trump White House Counsel is raising serious questions about the legality of Joe Biden’s final wave of pardons and commutations, urging the Justice Department and Congress to interview the former president’s advisors to determine if he truly authorized acts of clemency signed by an autopen operated by staff, according to a memo obtained Saturday by Just the News.

    “We believe that answering the questions above requires interviewing those involved,” White House Counsel David Warrington wrote in a memo to President Donald Trump’s Chief of Staff Susie Wiles. “As the WHC does not have the authority to conduct interviews, we recommend that you approve making the information contained in this memorandum and the supporting materials available to entities that do have that power.

    “By sharing this information with the Department of Justice and the United States Congress, we will be able to assist their investigations and provide much needed transparency to the American people,” the memo added.

    Just the News recently reported on bombshell internal White House memos that showed Biden had outsourced clemency decisions to then-Vice President Kamala Harris and allowed staff to use an autopen on late-term pardons even though staff believed at the beginning of his presidency that he needed to personally sign by hand such actions.

    The Warrington memo also called into question Biden’s claim to The New York Times this summer that the use of autopen was necessary due to the large number of individuals who received a pardon or clemency at the end of his presidency.  

    “This argument would make sense if, for example, President Biden was signing commutations or pardons for each individual receiving clemency. In reality, the materials drafted by Biden White House staffers contained lengthy lists of names and required only a few presidential autopens. The December 2024 commutation of nearly 1,500 individuals serving home confinement required only one signature,” the memo stated.

    “The January 2025 commutation of nearly 2,500 individuals for crack-powder sentencing disparities required only three signatures. WHC does not raise this solely because of President Biden’s obvious falsehood. Whether done for simplicity or due to President Biden’s diminished faculties, the practice of structuring pardons or commutations so that the fewest number of signatures would be needed created several problems,” the WHC wrote in the memo.  

    According to the memo, the White House Counsel found that Biden’s staff secretary was “unsure if the president had actually approved specific individuals for clemency” and that staffers could “add or subtract clemency recipients after President Biden’s alleged approval.”

    The memo said that “broad language meant violent criminals would be released” and broad language “would cause confusion for officials at DOJ responsible for processing pardons or clemency.” In the memo, the WHC said it found out that a Biden staffer said the president did not read the “warrants for pardons or commutations.” According to the memo, some of the questions the office wants Biden officials to answer include:

    “If a memo authorizing widespread autopen usage was written before President Biden was inaugurated, was staff already questioning his fitness to serve?”

    “If President Biden made every clemency decision, then why do his briefing books from December 2024 and January 2025 contain nothing of substance on the pardons or commutations he allegedly approved?”

    “If the President approved a pardon or commutation, why did staff often wait days before communicating the decision to anyone?”

    “Were staffers to Chief of Staff Jeff Zients and Deputy Chief of Staff for Policy Bruce Reed sending emails on their behalf regarding pardons or other issues without informing recipients?”

    “If President Biden was mentally fit to serve as President, why did he need cheat sheets explaining that he had approved commutations for 1,500 people or a pardon for his own son?”

    Liked by 1 person

    1. I just spent the last 2 hours helping hubby install the new dvd player.

      we bought this new one (same as the old one 3 years ago when this one went wonky–then it started playing just like it always did.)

      we tried everything–it’s the same dang player. we unplugged it and unplugged all the cords and then plugged them al back in and viola…it works. smh technology.

      Liked by 1 person

  24. “Trump is at War with the Enemy From Within”

    Clandestine, Sep 06, 2025

    “I don’t think the name change was just cosmetic. Trump is sending a message. We are going to war. But not with a foreign enemy. With a domestic one. Trump is at war with the “enemy from within.”

    The Dems intentionally left the border open so they could import tens of millions of voters to cheat in elections. Trump is going into sanctuary cities to deport these illegals and shut down their election fraud schemes.

    This is why the Dems don’t want NG/ICE in their cities. They know Trump is about to use the Department of War to cut off their life source, election fraud via the illegal vote, mail-in ballot harvesting, etc.

    I think Trump is sending us a message that he is about to go on offense against the Deep State.”

    Liked by 1 person

  25. Like

  26. Deep in the trackless forest, the bridge built by the ancient Lemurians still remains.

    Walter Davidson posing on his 1907 Harley-Davidson motorcycle

    Iridescent Clouds

    Liked by 1 person

  28. Tree Elves

    The Art Deco door. Entrance of a building in Paris, by Léon Tissie, the ironwork made by Adalbert Szabo

    Imagine sitting there and watching the storms roll in off the ocean

    Liked by 1 person

  32. we just got back from a short ride–into town to get the mail–nothing from Mom—sigh. then hubby wanted subway, so we drove two towns over so he could get a sub.
    on the way home, we noticed the neighbor–the retired air line pilot who built a huge summer home, just had his driveway paved. it’s as long as ours, but his place sits on the opposite side of the street–so he gets a lot of sunshine in the winter. our driveway is mostly in shade. must be nice to be rich though…lol

    Liked by 1 person

    1. Yeah – I agree about the being rich part – my dream is just to get a dump truck load of gravel spread on my driveway!!! LOL

      Liked by 1 person

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