Notes from the Trail

phenology

noun: phe·nol·o·gy  -- the study of cyclic and seasonal natural phenomena, especially in relation to climate and plant and animal life.

The changing of the seasons; it's a big part of our lives in northern Minnesota.  At Great Lakes Aquarium it factors significantly in what we do.  Phenology helps us understand and teach about the resident animals in our care and the migratory patterns of animals in our region.  It is also integrated, season to season, in the educational programs we offer, encouraging exploration and fostering a greater understanding of our natural world.

There is no better season to witness phenology here, in my opinion, than this one.  Autumn in Minnesota offers a spectacular show which arrives seemingly overnight in a silent explosion of color.  It's Mother Nature shouting at our eyes, "Be here now!"   

There are 176 miles of wooded trails in and around the city of Duluth, according to Outside Magazine. (Side note: In case you slept through the summer and hadn't heard, Duluth was named Best Town Ever by that publication for 2014.)

My personal favorite is the Superior Hiking Trail (SHT).  The nearly 300 mile footpath originates in Jay Cooke State Park, following the rocky ridgeline above Lake Superior's North Shore to the Canadian border.  A stunning 43 miles of the SHT cuts through Duluth and is easily accessible from a number of entry points. 

Today, the first full day of autumn, I picked up the trail at Spirit Mountain.  The hike offers dramatic vistas of the St. Louis River and is relatively tranquil (I had just a few brief encounters with students on field trips).

According to the Minnesota Department of Natural Resources, Duluth is between 25 to 50% of the way to peak color as of today.  

My personal report from the trail:  there's still plenty of green mixed with shades of orange and an abundance of wild mushrooms to spot and attempt to identify (beware, many varieties are poisonous or toxic).  Colors will likely peak in the next 7 to 10 days.

So, get out there.  Explore.

The rewards are awaiting.

A Ship(wreck)'s Log IV: Life Support Systems

An essential part to a successful aquarium.

Hello again and welcome to a Ship(wreck)'s Log. 

Things are really starting to heat up around here.We are now just a few weeks away from opening; the aquariums are in place, the exhibit construction is almost complete, most of our fish are in quarantine, and we have water in our tanks,but they are not quite ready for the fish.  

In this post I am going to tell you about the next step before placing the animals in their new homes. That step involves life support systems and Aquarium conditioning.

You may be able to keep a fish in a tank of water for a brief period, but sooner or later these fish are going to have needs to be healthy. Like us, fish need to breathe. Unlike us, who use lungs to get oxygen to our bodies, fish use gills.  A container of water will have a little bit of oxygen but the fish will use it up pretty quickly and we will have to replace it.  We will have to regulate the temperature, since fish are cold blooded the temperture of the environment is very important.  If we leave our water out too long it may become too cold or hot for the fish. The fish are going to get hungry and going to need eat, and as we all probably know what goes in must come out. These wastes will need to be removed from the water. Fish waste includes solids and nitrogen. One form of nitrogen is ammonia, and at very low levels ammonia can be very harmful to our fish. 

Now since we know that long term housing of our fish in the tank will not work let's explore how we will make it work. This is done using the life support system. 

Life support is another way of saying aquarium filtration.  We call it a life support system because this system makes the aquarium environment able to support life by removing waste and adding basics to the water like oxygen.

The first step in keeping our fish is a tank or aquarium. Our aquarium will hold water and, like our own homes,will have furniture to make the aquarium more comfortable for the fish ( more to come on that topic in the next post). 

Water in the aquarium

Next is the movement of water. The water has to flow from the aquarium to the life support system and back to the aquarium. This is called recirculating. In order to do this we use a pump to move the water and pipes for the water's path. 

Darin connecting the pumps to the sump

The author does his part :)

Connecting pipes to the aquarium

As water fills the tank skimmers at the top of the tank draw water out, down to the sump and life support system.  The sump is basically a large tank. The splashing of the water into the sump adds the oxygen and is where the pump pulls water from and pushes through the rest of the life support system.

The sump

The next step in our life support system is waste removal. As I mentioned earlier there are two types of waste that need to be removed; solids and nitrogen. To remove solid waste we use sand filters. The sand filters are large vessels about three quarters filled with a special type of sand. As the water flows through the filter the sand traps the solids much like a colander would trap spaghetti, and let the now solid-free water move through.

Sand filters

The nitrogen removal is a bit different.  Here we need help from bacteria, or more specifically, nitrifying bacteria. These bacteria will remove harmful nitrogen (ammonia and nitrites) through a process call nitrification. The end product will be a less harmful type of nitrogen (nitrate) that can be removed by water changes. We do have a specific filter for this called the bio-filter. A bio-filter is basically a vessel that will promote bacteria growth by giving the bacteria a place to grow and thrive. One type of bio filter that we will use is called a fluidized bed. This filter is somewhat like a sand filter in that it is a vessel partially filled with sand, but this sand is not used to collect solids. The sand is for bacteria to grow on and the water flows through for the bacteria to come in contact with the nitrogen in the water.

Fluidized bed

Since these fish will be tropical we need a way to heat our water so the next step will be a heater. We will be using a heater called an in-line heater, where the water will flow past a heating element on its way back to the aquarium.

In-line heater

We can now safely keep our fish alive with this system.  But since we are an aquarium, and we would like you to see the fish we add a couple more special filters to the life support system to ensure that the water is crystal clear. 

Though our sand filter is taking out the larger solids, smaller solids we call organics (which usually consist of algae) will be slipping through and making our water cloudy or green. So we use two types of filters to take care of these very small solids. These filters are a protein skimmer and UV filter. 

The protein skimmer is a filter that creates very small bubbles. These bubbles act like "magnets" which the organic particles will stick to. As the bubbles collect the solids they create a grimy foam that is lifted out of the water by the bubble action into a collection chamber. They are then removed from the system.

Protein skimmer in action

Protein skimmer and sump for Shipwrecks Alive!

The UV filter is a vessel that has ultra violet (UV) lights in it. The UV lights will destroy the cells of these organics. The broken down organics will begin to stick together, and are now big enough for our sand filters to remove them.

UV filters

Our Life Support systems have all been installed, the pumps are running and water is in the tank. But we are still not ready for the fish. Now we have to condition our tank.

The completed Life Support system

Previously, I mentioned that we have a bio-filter where bacteria will remove harmful nitrogen. Well, conditioning our tank means we are culturing bacteria. This naturally-occurring bacteria will already be in the water but we need to promote it's growth by "feeding" it.  We start by calculating how much nitrogen our fish will produce. The type of nitrogen the fish give off is called ammonia nitrogen. We then add the ammonia to the water using a powdered form and test the water. We know that the process is started when the amount of ammonia in the water drops as we are still adding it. As the ammonia numbers are dropping the byproduct of this process is nitrite. So as the ammonia drops,  nitrites will rise. Nitrites also can be harmful to fish, but lucky for us there is another bacteria that will remove nitrites and the byproduct of this process is nitrates. Nitrates are less harmful to fish and can be managed by regular water changes.This whole process can take up to four weeks. So our first priorities we have when putting in a new exhibit is making sure that our bio-filters are up and running.

Currently we are in the middle of this process, but the conditioning is almost complete and we plan to start adding fish soon. 

A healthy life support system is the most important step in keeping healthy happy fish. Next time you are at the aquarium and you see the fish swimming by, I hope you will have a better understanding of what goes on behind the scenes to keep things swimming.

The next post we will explore putting the "ship" in Shipwrecks Alive!

Jay

. 

A Ship(wreck)’s Log III: A Zebra Shark Tale

We recently received a large shipment of animals from a supplier in Cairns, Australia.  This shipment included many of the fish species that will be on display in our new Shipwrecks Alive! exhibit, including a Tassled Wobbegong, a Black-Blotched Porcupine Pufferfish, an Orange Spotted Grouper, some Spotted Unicornfish and many more.  

Black-blotched porcupine pufferfish

Orange spotted grouper

The star of this shipment, however, is a gorgeous female Zebra Shark!  She is approximately 5 feet long and weighs about 30 lbs, and she’s still not done growing.  She is what’s considered a sub-adult and will eventually reach a length of 10 feet!

Zebra shark

So you might be wondering, how does a 5 foot long shark get all the way from Australia to Duluth?  Well, let’s start at the beginning.  Late in the evening of February 4, 2012, a Zebra Shark was born at Reef HQ, a public aquarium in Queensland Australia.  Our little “pup” (that’s what a baby shark is called) was hatched from an egg after an approximately 4-6 month gestation period.  Zebra sharks are oviparous. This means the pups develop outside of the body. The eggs are protected by egg cases with hairy-looking fibers all over the outside which help to attach the egg case to corals or seagrass and keep it from floating away. They can be about 8 inches long and Zebra Sharks will lay about four eggs at a time.  The pups actually have stripes when they’re born (hence the name Zebra Shark).  As they grow older, the stripes fade and they develop a spotted pattern.

Our zebra shark is showing a spotted pattern

Now getting back to our shark - she spent the first year of her life growing up at Reef HQ and was then sent to Cairns Marine, a fish wholesaler in Cairns Australia.  She lived at their holding facility for another year, eating and growing like crazy, until we called up Cairns looking for, you guessed it, a Zebra Shark!  After working out all of the details, Cairns packed her up, along with the rest of our fish and sent her on her long journey to us.

She was packed in a large shipping container filled with water, lots of oxygen, and a pump to circulate the water and air in her container.  Then she was put on a plane as cargo (yes, fish are commonly in the cargo holds of commercial planes – think about that the next time you fly!).  The plane went from Cairns to Hong Kong, then to Los Angeles.

Large shipping container from Cairns, Australia

Individual, smaller shipping containers

The large orange-spotted grouper traveled in its own container

  Because the travel time was so long, a water change needed to be performed so that water quality was within safe limits for the shark.  So we enlisted Consistent Sea, another fish wholesaler in Los Angeles, to assist us.  They got our shark through U.S. Customs (just like any other international traveler) and brought her back to their warehouse for a water change and fresh oxygen.  Finally, they repacked her and sent her on another plan from Los Angeles to Minneapolis, and our staff collected her and the rest of the animals at the airport and headed back to Duluth.

Once we got the animals back to the aquarium (at around midnight!), the real work began. Whenever a fish is moved from one water body to another, acclimation must be done.  This basically means that we exchange water from the new tank to the tank or shipping container that the fish is in until both are as similar as possible.  During acclimation, we closely monitor things like temperature, pH, oxygen levels and salinity to make sure our fish stay healthy and to determine when they’re ready to go into their new tank.

Tomato Hind being transferred to acclimation tub

Operations manager Jay Walker netting grouper from shipping container

  When our Zebra Shark was ready, we carefully moved her from her shipping container into her quarantine tank with a cloth stretcher designed to move large animals like sturgeon and sharks.

Zebra shark acclimating

The Zebra Shark will live in her quarantine tank in our Holding area and will go through our standard quarantine treatments to prevent bacterial and parasite infections.  Another of our quarantine protocols for our sharks is to get them to eat directly from us using tongs.  Luckily, since this particular shark was born and has lived in captivity her whole life, she has already been trained to come to people for food – which makes our job much easier!  She, along with the rest of our new arrivals, will remain in Holding until our new exhibit, Shipwrecks Alive, is completed.  Be sure to visit her and her tank mates when the exhibit opens in July!

Anang's Retiring!

If you've read any of our previous blogs on Anang, or Haley as I like to call her, you know she has recently been in her holding space recovering (beautifully!) from a fracture in her fibula. She has been doing great. She is as active as she can be, and always up for new enrichment.

 (Haley, or Anang, playing with paper towel rolls in her holding space.)

Did you know that otters in the wild usually live to be about 10 years old? Haley is 17! In captivity otters can live to be up to 25, but usually 18 years is more common. The oldest North American River Otter in captivity just passed away recently and was 21 years old. Otters can live so much longer in captivity due to their daily care, veterinarian checks, dental cleanings, and well rounded diet. 

Old otters can suffer from many of the same ailments as people can! Haley has arthritis in her back hips, and has for many years. She seems to be thriving in her holding area, which is really flat, with an in-ground pool that has easy access. 

Since she seems to be doing well, her animal care staff has decided she will be retired from her exhibit, so we can give her a comfortable, flatter space to live in. She will remain at the Great Lakes Aquarium for the rest of her life. We are hopeful that she will live in our downstairs holding area for a few more years. 

Many of you are probably wondering if she will ever get any otter friends or be introduced into another roommate. And the answer to that is no. She has seemed to really enjoy her time here alone, after Zhoosh (Clyde) passed last summer. She was so active and played so much, we had to continually up her diet to keep up with her metabolism! And, in the wild, females generally wouldn't make new friends at her age (or an age comparable to hers in the wild, maybe 8-10). Females would stay with their families or else just go on by themselves. North American River Otters are not the most social of all of the otter species. Most males will live on their own for most of their lives, and females will stay with their family until breaking off to go on their own. So Haley's instincts are to be alone, and she seems to be happy being alone.

 (Being her super cute self!)

Fortunately, her holding area will be visible to all of the behind the scenes tours. She will be moving to the space before the summer months, but the actual date is still unknown. 

The space will accommodate her aging body in many ways. It is really quite flat, with ramps to get to any elevated areas, instead of steps, and has a nice size pool for exercise. Because of her arthritis, it is best to give her some space for exercise, but not too much to make her joints more sore. 

We are excited for her to move to this space, and we hope that you will come visit her on our behind the scenes tours! 

 

(Enjoying her mackerel, which she had to pull out of the red ball to the right! It took her almost ten minutes!) 

Here an otter, there an otter!

The staff at the Great Lakes Aquarium is excited to tell you that we have two new resident North American River Otters! 

 

These two otters have come to us from DuPont, Louisiana. Together, they were trapped in a crawfish farm by a local trapper. They had been eating the crawfish at the farm, and had become nuisance animals. North American River Otters are not endangered or threatened, so in this case, these two otters would have been lethally trapped. Another man paid the trapper to live trap them and then he brought them to his space, where he holds otters until they can be placed in a zoo or aquarium setting. Demand for North American River Otters is high, so he holds them usually only for a few weeks. 

 (This is shortly after we got them. You can see their transport crate with the MSP label on it!)

We found this man through an otter specialist, and he came highly recommended. Other well known zoos and aquariums have also gotten otters from him. 

(We had put out a request on the official list for placement of any otters that needed a new home, and we had also contacted many, many wildlife rehabilitation centers and individuals. Last year, we heard of only two otters (in the US) that were rehabbed and placed in captivity; all the rest were released! That is great, and the point of a rehabber.)

Within only two weeks of contacting the source, Heidi (the curator) and I were headed down to the Minneapolis-St. Paul International Airport to pick them up. They were each in their own wooden crate, with holes along the top for air flow, but very little visibility. That can be scary for an animal that has no idea of what is going on. A gentleman with a forklift put them in our van, and we got on our way. 

Upon arriving to the Great Lakes Aquarium, we unloaded them onto a cart and wheeled them inside our holding area. We weighed each crate with the hopes of getting a weight for each otter once we could weigh their crates, eventually.  We placed a few piles of fish outside their crates and then pulled the doors off. We left the room and watched from behind the window. They came out within a few short minutes and ate right away. Then, the took a few drinks of water and explored their surroundings. 

Heidi worked with them alone for about a week so they would get used to her coming in with food and not being too scary. She fed them 2-3 times per day. Then, once they were ready to eat right through the bars of their area, I started helping to feed, too (it is much easier to each feed one otter!). 

 (Curator Heidi is feeding one through the bars of the holding space.)

It is really important with any new animals, including our pets, to earn their trust. We wanted them to know that they are safe here and we won't hurt them. We let them dictate the speed at which we work. It took until day 8 for me to start feeding with Heidi because the day before they showed her that they were starting to trust her by eating from her hand or coming right up to her on the other side of the bars. They also have each chosen their "station" of where they want to eat, and they will go there every time we go in with food dishes. This is telling us that they know how to learn and how to target. We will target train them so we can build on that basic training. (Target training for an otter means we hold a target and when we ask them to target, they put their nose onto the target.) If they respond to target training, they can be targeted to a scale, into a crate, or to move elsewhere. When they are ready to go inside a crate and have the door shut, we can move them upstairs, to the holding area off the exhibit. They  will dictate the speed at which everything is done. 

So, you are probably wondering what they are like, how they look, and all sorts of things about them! Firstly, we are told (by the man who kept them until we took them), that he thinks they are both females. At this point, because it isn't breeding season, if one is a male, we won't know yet. Also, their thick fur and skin folds prevent us from determining their sex clearly. So, at first I was calling one "the brave one" or "Clyde junior". She looks a lot like a mini Clyde! The other one is more shy and took a few days longer to warm up to us. I call her "the shy one". But now, it is almost hard to tell which one is brave and which one is shy! But, one (the "shy" one) is a bit darker, just a tiny bit, and has ears that stick out a bit more. She also has beautiful white, sharp, large teeth! The other one has smaller teeth. (We are hoping to use their teeth to help determine their ages.) They love to eat! They are still getting used to toys and blankets, but they like to carry straw around, make beds, and a huge mess! They are already really comfortable in their space! 

 (This is the one that was more shy at first. She is getting a shrimp off of the plastic duck toy.)

 (This is the one that has always been a bit more brave. She is eating a shrimp.)

We hope to have some sort of public naming contest or public participation in their naming. Most likely, we will start after the public gets to see them on exhibit. To keep up with the latest information on how they will get their names, please check our Facebook page, our website, or future blog posts!

And, as the time draws near to when they will make their first appearance on the exhibit, we will make sure to get the word out as much as we can so everyone can come see them! 

We hope you are as excited as we are to welcome them to our facility!

A Ship(wreck)'s Log II

Hello, again. I am so excited to bring you the next installment in A Ship(wreck)'s log. The last few weeks have been a flurry of activity. So let's raise the sails and begin.

Our construction team has renovated the exhibit hall to give us 250 more square feet of exhibit space, and completed the platforms for our aquariums. The aquariums are currently being built in California  and will be here in the next couple of weeks.
One of our aquariums will hold 10,000 gallons of water and is 18 feet long. The other aquarium will hold 4,000 gallons of water and will be 16 feet long. The platforms have to be pretty strong because our largest tank will be 80,000 pounds. Now since the platforms are finished the construction team can start building the rest of the exhibit.

Gary and Tom are constructing the platform for the ancient shipwreck display. This platform will hold the 10,000 gallon aquarium.

This platform is for the 4,000 gallon Pacific wreck.

Here's an example of exhibit walls.

Gary is doing some research on a curve at the top of one of the exhibit walls. This wall will be part of a graphic display for the Pacific Wreck exhibit.

Working on opening up the space.

Our husbandry team has been receiving new fish for the exhibit. Many of the fish we have come from accredited suppliers and from other zoos and aquariums.  But our newest residents are fish which were pets that became a bit too big for their homes.
Word to the wise, always do research on an animal before you buy it. I have seen many situations where adorable little fish have grown into over-sized predators . So make sure that the animal is a good life-long fit for your aquarium.
Here's a good example. One of the fish we received is a juvenile nurse shark. The nurse shark can grow to 14 feet as an adult and is a literal fish vacuum, so be wary.

This Nurse shark is very curious and is loving her new temporary home.

Hello from the Peacock grouper

This is one beautiful panther grouper, and I think he knows it.

In the next couple of weeks we will be finishing the installation of our filtration system and placing one of the new aquariums.  So make sure to look for the next installment of a Ship(wreck)'s Log, because it is really going to be exciting.

Until next time, fair winds and calm seas!

Jay