Monday, March 11, 2024

Cannibalism happening in tanks across the region

A bigger trout digesting a smaller trout in a tank at a Union Springs classroom in 2015


It seems every year, we hear of reports of cannibalism in trout tanks across the region. Sometimes there is a suspicion that cannibalism is happening, as trout seem to be "disappearing" from the tank, and one or two trout are abnormally larger than the rest. But sometimes, students actually see a larger trout eating a smaller one in action, as they will spot a fish tail hanging from a trout's mouth. 

Trout, like many fish are cannibalistic and will likely eat smaller members of their own species. This is an example of natural selection, as some trout are better at adapting to their environment. 

When visiting schools, I always ask students for an update about what's going on in their tank, especially since they are spending a lot more time interacting with their trout aquarium than I am. One of the first things I usually hear about is the possible cannibalism happening. I often ask students why they think this is happening. Then I'll ask them which kind of trout has a greater chance of surviving in the wild, the small trout or the bigger trout that is able to eat the smaller trout?

A trout that has moved beyond small, dried up fish food and is able to capture live, moving fish in their environment indicates smarter, faster, more agile behaviors. Wouldn't a fish displaying these behaviors have a better chance of fighting off future predators like bigger fish, otters and birds of prey?

An angler in Strawberry Reservoir in Utah found a partially digested fish in the mouth of a cutthroat trout. Brett Prettyman/Trout Unlimited 


 

Monday, March 4, 2024

March: A time to think about clean water and individual actions






Spring is just around the corner! Which has us thinking about the upcoming trout releases. And as we begin planning for the releases, one building block to the student's Trout in the Classroom experience is understanding the importance of caring for the trout's environment once they are swimming in local streams. Which is what this month's Watershed Pollution Prevention lesson is all about! 

During Visit #4: Watershed Pollution Prevention, we will present on topics including water cycle and watershed so students can gain an understanding of how pollutants can enter into a watershed. Then we will look at different types of pollutants and how they can eventually be harmful to trout, the food web, and the natural ecosystem once they make their way into the water. 

Students identify pollutant actions, with a particular focus on trash, pesticides, fertilizers and ways natural landscapes can increase or decrease run-off. Once they have a good grasp of harmful pollutants, how they make their way into a watershed, and the damage they can do to aquatic life, it's time for the class to conduct their own watershed pollution survey!

Groups of students use a pollution scavenger hunt worksheet to examine their school campus for signs of pollution hazards and pollution preventers. At the end of the hunt, students score their school and its process of eliminating or adding to watershed pollution. This has led to conversations about problems students noticed in their school, or awareness of positive school behaviors. It's great to see student's brain's working to come up with solutions, or goals to continue to prevent pollutants from entering waterways.

The pollution prevention lesson is happening during a convenient month for continued education on topics related to pollution prevention and watershed awareness. March 18th is Global Recycling Day, which brings awareness to recycling as a way of protecting natural resources. This year's theme is #RecyclingHeroes. Here are some great examples of rising youth stars who's bright ideas and initiatives have made a difference in local and global recycling efforts. 


As we visit 20+ schools in the region teaching pollution prevention, we often hear insightful ideas students have about protecting local streams from pollution. Students participating in the Trout in the Classroom program have a great opportunity to be environmental advocates in their community, as they learn trout's habitats needs and understand the importance of clean natural waterways for their trout to continue to live and thrive!


March 22 is World Water Daywhich is a great time to ponder inequalities to clean and accessible water worldwide. Here are three activities put together by UN Water for school kids of all ages to learn about water conservation and peace building. Explore these concepts with your class through engaging and fun activities like art and even football! 


For a local way of engaging with conservation, students are invited to join Ithaca Fishing and Conservation Day is happening Saturday, March 23 at Boynton Middle School. The event is put on by Trout Unlimited and Discover Cayuga Lake will be there to do science activities with students. 


Tuesday, February 6, 2024

What would your trout would be doing in the wild right now?

We've been observing our trout hunting and eating zooplankton in captivity, but what about all the baby trout in the wild? Will they have the upper fin in hunting and competing for food when we release our captive trout? Is a winter stream environment a nurturing habitat for baby trout? Let's find out!

A baby wild trout has about 4 months of life in its stream habitat by this time in February and is known as a trout "fry" or "parr." Check out this cool video to see what a brook trout parr looks like at this time of year!



Here are some cool facts about wild trout parrs and how they grow up: 
  1. A wild trout parr will be smaller than a trout parr raised in captivity. This is because growing up in the wild is typically colder than growing up in a tank, the water can even be a temperature that would normally cause water to freeze if the stream is running fast enough! The colder the water a trout grows up in, the slower the trout will grow. 
  2. Stonefly larvae in June 2020.
    A wild trout parr starts hunting almost right away as soon as it can swim, and sometimes even before it can swim! While our captive trout learn to come up to the surface of the tank and beg for food, a wild trout looks for its food at the BOTTOM of a stream. This is called BENTHIC feeding and means that trout grow up mostly eating stonefly, mayfly, and caddisfly larvae that can be found hiding among the rocks of healthy streams. 
  3. A wild trout parr will hunt and eat zooplankton, just like we watched with our captive trout in our recent feeding experiments! Wild parrs don't typically eat Daphnia (the zooplankton we fed our trout), but they do eat a different species of zooplankton... known as copepods. In fact, a common copepod that trout like to eat is called a calanoid and might look like a Plankton you've seen before (hint: Spongebob).
    Calanoid, a microscopic zooplankton.
So what do you think? Who has the upper fin? A trout that has grown up hunting and spent its whole life in the wild, or a larger trout that doesn't have as much experience hunting or hiding among the rocks? 

-Originally posted by Marina Howard, March 17, 2021

Monday, January 22, 2024

Some Cool Facts About Daphnia!

Daphnia are a zooplankton, meaning that they are animals (zoo) that live at the water's surface, drifting with the currents (plankton). But daphnia are not just any zooplankton... they can live in incredible conditions! 

Studies show that daphnia can live in slightly salty water like you would find where a stream meets an ocean (estuary) and that they manage small levels of salt just as well as completely freshwater! This is incredible. If a human were stranded on a boat in even mildly salty water, they would not be able to survive drinking it because the salt would just make them thirstier - but daphnia can. 

A healthy daphnia (left) with a daphnia
producing hemoglobin (right).
 

And here is something even more incredible: if the water source is not changed for the daphnia and they start to use up all their oxygen, they create the same chemical that we have in our blood (hemoglobin) to bind oxygen - making their oxygen intake much more efficient (and turning them slightly reddish colored). That's crazy! Think if you were trapped in your classroom without an air supply and everyone breathing up all the oxygen, pretty soon you would feel super lightheaded, but daphnia have a mechanism to be able to survive days longer in an environment without a lot of oxygen.

If you think that is cool, just wait until you get to watch a trout chase a daphnia around a glass in our feeding experiments. We will have videos and more results of our live feedings coming by the end of next week, stay tuned!

You can check out more about daphnia through our worksheet and a slideshow shared by our teacher program on the teachers' tab of this blog. 

-Originally posted January 29, 2021 by Marina Howarth

Daphnia heartbeat




Tuesday, January 16, 2024

First Live Food Experiment!

Our young trout have grown to a size of about 2 or 3 centimeters in their "parr" stage. Are they ready to hunt and eat living prey? At this point in the year, classes are ready to conduct their first "live food" feeding experiments, using a common zooplankton, called "Daphnia". 

First, students have a chance to practice observation skills, as they get to know the "costar" of this experiment. Daphnia are about the size of a sesame seed. 


Then, student research teams prepare their hypotheses and perform an experiment to see how their trout will respond to an opportunity to try a new food... that just might try to escape! 




Finally, students evaluate their results and compare with other research teams. Here is a typical chart that depicts how many daphnia are eaten by trout during 20 second intervals over five minutes. Interesting... for more on this lesson and teaching materials, click on the "For Teachers" tab!





Monday, December 11, 2023

How to know when your trout are ready to start feeding?



If you are uncertain whether it is time to begin feeding starter food to your trout, watch for these behaviors below to determine if its feeding time:

WHEN TO KNOW TO FEED? When trout have absorbed their yolk sac, they no longer have a source of nutrition and will start to need food. They also are developing their swim bladders, as you may notice the trout have been hanging out at the bottom of the net, not swimming. When their swim bladders are developed, they will become buoyant and will start swimming around. Once these two things have happened (yolk sac gone, swimming behaviors) then your trout will be ready to start feeding.

HOW TO TEST IF YOUR TROUT ARE READY TO FEED: Sprinkle a tiny pinch of starter food in the basket, if they are not reacting, they are not ready. If they get more active but do not eat, they are reacting to smell (getting close.) Can you observe them feeding? Great! When it seems like all or most are feeding successfully, you can keep them in the basket for a few more days or drop the basket from the side of the tank and let them swim out.

HOW MUCH DO I FEED THE TROUT? Feed a few pinches at a time, multiple times a day.

Monday, November 27, 2023

Overview of Trout in the Classroom Program 2023-24

Overview of Trout in the Classroom Program 2023-24

Fall 2023 TIC Teacher Workshop


Discover Cayuga Lake coordinates over 20 schools throughout Tompkins County and surrounding counties participating in the Finger Lakes Trout in the Classroom Program. The program enables students to raise trout in tanks in their classrooms from October- May. Students learn to care for their trout and learn about streams through science, art and language. Just as they learn to take care of their trout, we hope students will continue to care for their newly adopted streams.


  • October/November: Eggs arrive 

  • November-April: Care for your trout, observe and experiment

    • Trout Stages:

      • Eggs

      • Alevin

      • Fry

      • Fingerling (when released)

      • Adults

  • April/May: Trout release field trip


Discover Cayuga Lake provides 5 presentations throughout the Trout in the Classroom Program. Mentors are assigned to schools in order to educate classes on their trout and stream ecology while supporting classes as they help keep trout healthy and thriving. Katie Barnhill will oversee the FLX TIC Program, alongside other class mentors including Bill Foster, April Taylor and Astrid Jirka. You can schedule your presentations with us through our 2023-24 scheduling spreadsheet.

 

The 5 presentations include:


  • Visit #1: November: Kick-Off Program (Browns)/ Brooks: Overview of trout life cycle, understanding the parallel connection between hatchery egg retrieval and natural spawning process happening outside right now. 
    • Main Objective: Help students feel confident in raising trout by answering questions about life cycle, caring for trout and what to expect throughout the year.
    • Activity: Could view eggs up-close under microscope/in petri dish at table if time allows. 
    • Further Activity

 

  • Visit #2: December: Color & Adaptations: Trout are equipped to survive in the wild through adaptation. Trout can change their appearance in order to camouflage within their stream habitat. Learn the different types of camouflage including: Concealing, Disruptive & Countershading.
    • Main Objective: We can tell a lot about fish by observing their habitat, also we can learn a lot about habitat by observing fish.
    • Activity: Students imagine a place and a stream and then illustrate a trout using elements of camouflage to blend in with its habitat. Students share their trout illustrations with class. The class can try to guess the features of the trout’s habitat based on the camouflage features illustrated on the trout.
    • Further Activity: Trout Survival Game

 

  • Visit #3: January: Live Food Experiment with Daphnia: Students use the scientific method to answer the question, “Do you think your trout will be able to catch and eat live food when they are released into the stream?” Students will learn about the live food used in the experiment, daphnia, by first learning about the aquatic food web and the important role of zooplankton. Then students will test how many daphnia their trout eat in a given amount of time. They will discuss results of their experiment, revisit research questions and draw conclusions about whether their trout will eat live food and survive in streams.
    • Main Objective: Use the scientific method to draw conclusions about the trout’s ability to survive when released into a wild stream.
    • Activity: Live food experiment. Students will be given a research question, “Will my trout eat live food,” and go through the scientific method to conduct hypotheses, test with an experiment, analyze results and draw conclusions. The experiment includes feeding daphnia to the trout with a beaker on their desk. Groups of students will record how many trout are eaten every minute for a 4 or 5-minute span of time.
    • Further Activity: Students can plot data from their live food experiment, classes could add all of their data together with a sum of all team results, and analyze/draw conclusions about research questions from class data. This could also be compared/shared with other classes/schools.

 

  • Visit #4: February: Pollution Prevention and Watershed Awareness: Students identify watershed pollution problems by learning about the water cycle and how pollutants can move through and impact aquatic plants, animals and humans in a watershed.
    • Main Objective: Understand how water moves through a watershed and learn how pollutants can enter a watershed and harm aquatic life, the environment and humans.
    • Activity: Students being school pollutant detectives, by selecting a pollutant topic of interest and conducting a survey around their school. Student groups will collect data about potential pollutant problems in their school, research how the pollutant can make its way into a watershed and how it can harm aquatic life, the environment and humans. Students will begin seeing themselves as a part of the solution as the group brainstorms ways they can educate classmates through projects that serve to persuade, entertain or inform their audience.
    • Further Activity: Follow through with enacting a solution in their school, based on student group’s pollution solution project
  • Visit # 5: March/April: Stream Ecology: Students brainstorm about indicators of a healthy stream and learn about insect life cycles and the stream energy web before conducting a live macroinvertebrate experiment. In the experiment, students will assess the health of a stream using a stream sample brought into the class containing live macroinvertebrate samples. Student groups will collect and identify insects and then score the stream based on the diversity of macroinvertebrates found. 
    • Main Objective: Learn about food webs and sensitive creatures. Use stream invertebrates indicators to determine the health of a stream.
    • Activity: Student groups will be given a container with a fresh stream sample. They will collect a diverse sample of macroinvertebrates in an ice cube tray and work together to identify the insects they collected. The class will come together with their data to score the stream's health based on biodiversity and identified insect’s sensitivity to pollution. This will prepare students to use insects as indicators to assess the health of the stream when they release their trout. 
  • May: Trout Release Field Trip: Students will take a field trip to a nearby selected stream to release their trout. They will first participate in activities to assess the health of the stream before the release, including collecting a macroinvertebrate sample, taking an intentional and observational stream hike, and conducting a trash clean-up around the stream. A journal or illustration activity could also take the place of a trash clean-up if not applicable. 
    • Main Objective: Students will have made a connection with their trout and learned about the conditions needed for the trout to survive in a stream. The hope is students will walk away wanting to continue to care for their trout by caring for the stream it now lives in and its surrounding environment and watershed.
    • Activity: Stream hike, macroinvertebrate sampling, trash clean-up, journal or illustration activity, group trout release.

Discussion Questions:

  • How can we make these core presentations more relevant to your classes?
  • How can we maximize the value of each presentation?
  • Any questions or ideas about ways to further engage with these presentations? Any obstacles?
  • Experienced TIC teachers- What do you wish you knew when you first started the TIC program?


Further Curriculum Dive:


Tuesday, November 21, 2023

How Can Climate Change Effect Our Trout?

With the help of our pals at the US Fish & Wildlife Office in Cortland, NY (Big thanks Justin and Gian!), we delivered BROOK TROUT eggs to nine aquariums at Dryden High School, Dryden Elementary School, Northeast & Caroline Elementary Schools (Ithaca, NY), Lehman Alternative School and Elizabeth Ann Clune Montessori school on Thursday, November 16.

The eggs in your aquariums are (or were) less than 1/4 inch in diameter, but even so, it was easy to make out two black dots in each- the eyes of the tiny fish inside!   These eggs were "eyed up", as the shells had already begun to thin and soften in preparation for hatching.  The big question on everyone's mind was, "how long will that take?" 

Suzanne Scheuring's students at Dryden High School wondered if there was a scientific way to predict when the eggs would hatch.  So, we put the question to Ryan Diehl, the hatchery manager at SUNY Morrisville's hatchery who provided our brook trout eggs.  He confirmed that, yes, you can predict the time between egg spawning (when the eggs are released and fertilized) and egg hatch.  

It is almost entirely dependent on the temperature of the water!

Ryan shared this table, from the US Fish & Wildlife Service's Fish Hatchery Management Handbook (1982), that provides information for both brook trout and brown trout.


We can see that for BROOK TROUT, the period from spawning (egg fertilization) to hatch is 144 days if the water averages 35 degrees F, but only 44 days if the water averages 50 degrees F.   Ryan shared that our eggs were spawned on October 12.  So, if we keep our aquarium temperatures close to 50 degrees, they should hatch about 44 days later - Nov. 25 or 26, just in time for Thanksgiving Break unfortunately!   Let's find out if they have hatched when classes return after the break!

Of course, in the "real world" outside, stream temperatures are much colder, as winter approaches, and are likely to be closer to 35 degrees than 50 degrees.  So brook trout eggs in a natural stream might not hatch for another 100 days under "typical" winter conditions.  That could be mid-February, which is actually perfect timing.


Our trout are born with a built-in energy supply, called a "yolk sack", that can nourish them for quite some time.  This is a perfect adaptation for being born in the middle of winter, when food is scarce.   If all goes according to nature's plan, by the time the yolk sack is used up, spring will have arrived and food will be plentiful for our hungry young trout.

Now that we know a bit about what effects the development of our trout eggs, what would happen if climate change caused our streams to become warmer throughout the year?   


Here's an example:  If average winter stream temperatures rise just a few degrees, to an average of  40F, for instance, our trout could be born in December, rather than February.  The yolk sack is not a bottomless buffet, however, and only will last so long.  What could happen to our trout? 


You can do a little of your sleuthing, to find out if climate change is already impacting our local trout habitat, or your favorite stream, by heading over to the Community Science Institute's amazing Water Quality Dataset that shows data collected by volunteers over the past ten or more years.  Just select your favorite stream and have a look!  

Monday, November 20, 2023

A Trip to the Hatchery!

We recently kicked off the 2023-2024 Eastern Finger Lakes Trout in the Classroom program with field trips to collect brown trout eggs at the NY Dept. of Environmental Conservation (DEC) state hatchery in Bath NY. Students from South Seneca Elementary visited the hatchery on Friday, Nov. 3 and students from Beverly J. Martin Elementary in Ithaca visited on Monday, Nov. 6.

Chuck, one of our knowledgeable the hatchery specialists, starts off the tour...Chuck, one of our super-knowledgeable hatchery guides starts off the hatchery tour....

Bill and Astrid help students get ready to collect trout eggs in the hatch-house!


Students collected sets of about 120 eggs (transferred to mason jars for transport) for 16 schools that will be raising brown trout this year!  All together, they collected nearly 2000 eggs!
It was a busy day for our brown trout, as many actually hatched on the way  to their new classroom environments.  Just imagine popping out of your egg, moving to a new home, and having your first class, all in just a couple hours! 



Of course, not all the fish at the hatchery are quite so small.  Students got to feed these hungry yearlings that will soon be releases to local streams.




Stay tuned to learn what happens next!