Building a Hydrophone

Building a Hydrophone

Building is a fun project to complete.  With a little guidance, anyone can make one.  If you want to build a hydrophone, read on. 

You can find the written directions here and video directions here.  

Materials List

You can order the following items from McMaster-Carr.  Here is what your shopping cart with look it.

Click the links below to order your items.

Stereo Cord

Male x Male, 25 Feet Long

https://www.mcmaster.com/#8317t15/=1e2jk7e

Epoxy Structural Adhesive for Vertical Surfaces 0.47 oz. Syringe

https://www.mcmaster.com/#7670a22/=1e2jlrb

Polyethylene Foam Adhesive-Back Bumper 3/4" OD, 1/16" High

https://www.mcmaster.com/#8213k2/=1e2jmqd

Standard-Wall PVC Pipe Fitting for Water Bushing Adapter with Hex, 1 Socket Male x 3/8 NPT Female

https://www.mcmaster.com/#4880k826/=1e2jn5k

Compact Plastic Submersible Cord Grip

Continuous Flex, NPT Threads, for 0.08"-0.24" Cord OD

https://www.mcmaster.com/#69915k62/=1e2jnle

From SparkFun

Piezo Element

https://www.sparkfun.com/products/10293

From Amazon

Voice Amplifier

https://www.amazon.com/gp/product/B071YVHLRP/ref=oh_aui_detailpage_o03_s01?ie=UTF8&psc=1

Tools

·         You will also need a few tools.

• ·         Wrench
• ·         Wire Stripper
• ·         Electrical Tape
• ·         Scissors
• ·         Rubber Gloves
• ·         WHOI recommended a soldering iron kit to connect the wires

If you would like to attempt to record data using the hydrophone, you will need a few other things

NIOSH Sound Level Meter iPhone App.

Microphone Input Connection for iPhone

You need a microphone adapter with a TRRS or 4 conductor wiring configuration (something that only apple uses and recognizes).  We also read we need a CTIA  instead of an OMTP wiring configuration.  We are still on the search, but will update this post with an adapter that works.   

Troubleshooting

Microphone Input Connection for iPhone

We ran into a few problems when attempting to collect data using the hydrophone.  We attempted to connect the hydrophone to our iPhone using several different adapters and have yet to find a compatible input connection so that the app NIOSH will recognize our external microphone.  It is important to collect the data only from our hydrophone, otherwise you will collect data around you using your internal microphone on your iPhone instead of data under the water. 

We think we have found the problem. We are currently looking for a splitter with a microphone input connection that is compatible with iPhones.  The NIOSH app is only built for apple devices.  Therefore you need a product with a TRRS or 4 conductor wiring configuration (something that only apple uses and recognizes).  We also read we need a CTIA  instead of an OMTP wiring configuration.  We wrote the developers of the NIOSH app at EA LAB, and they confirmed that we have yet to find the correct adapter.

We have tried several options that did not work.

Lightning to Headphone Jack: This option only changes the connection from a 3.5 mm headphone jack to a lightning connector

iRig Pre HD: This option allowed us to use the hydrophone as a microphone and record sound on our iPhones.  Unfortunately, the NIOSH app did not recognize it as an external microphone.

Splitters: We also have tried two splitter options.  One of them was OMTP.  Another, we thought would work, but we did not read the fine print.  It stated it was compatible with iPhones and it was CTIA, but I later saw it also said not TRRS.  One of the issues we ran across is these types of splitters are not sold in stores including Best Buy.  

Accurate Decibel Levels

Another question we have concerning collecting data using the NIOSH app and the hydrophone is, will we able able to get an accurate decibel level?

We are not sure how the microphone will accurately receive the decibels levels and transmit them to the phone because the sound that the microphone picks up is always quieter than the actual sound.  We also learned that some homemade hydrophones work better than other.  Would different hydrophones give you different decibels levels?  When researching our microphone input connection and the NIOSH app, we read articles on how important it is to have a good quality, calibrated microphone.  

Quality of Materials is Important:

Our second hydrophone had much better sound quality.  It may have been due to building experience, so if you are not happy with the first one try again.  We also changed the place we ordered the stereo cord and Piezo Element from.  Due to a shipping issue, we ordered our first Piezo Element and stereo cord off of Amazon.  For the second one, we ordered the Piezo Element from SparkFun and the stereo cord from McMaster-Carr.  It seems to us that the tricky part is adding the epoxy at the end.  Before adding the epoxy, you test out the hydrophone and we noticed a difference in sound right away.  This was confirmed when we tested both hydrophones out next to the bike ferry in Menemsha.  

Sound Pollution

While collaborating with WHOI this year we learned about sound pollution.  As you know, our goal this summer is to build a hydrophone that can record underwater sounds.  Researchers want to study these underwater sounds to determine the effects of sound pollution on marine life.  Sound pollution is a relatively new topic that is being discussed by marine biologists. We read multiple articles on the possible effects of sound pollution.  One article discussed how sound pollution might affect coral planulae. Coral planulae are free floating coral in the larva stage.  Although planulae do not have any ears, they have something called cilia, tiny hair-like structures that can detect sound in water. Planula use different environmental indicators to pick a location to settle in.  One of these indicators is the presence of CCA (crustose coralline algae), a type of algae that contributes to favorable habitats for coral. A planulae’s choice to settle on live CCA can be altercated when there is sound pollution such as boat traffic.  In the study below, when sounds recorded from marine protected reefs or MPA were played it increased the chances the planulae would choose live CCA while when boat noises were played it significantly decreased the chances the planulae would choose live CCA.  As you can see from the results of this study, it suggests that noise pollution could be a potential hazard to coral reefs.  Another topics I read about was the effects of noise pollution on marine animals. Some of the possible effects of sound pollution on marine animals are that it could change their behavior, prevent them from hearing important sounds, and also impair there hearing, sometimes permanently. Sometimes in the case of marine mammals these noise could increase marine mammals beaching themselves.

To learn more about sound pollution and underwater sound acoustics check these website.  

https://dosits.org/

https://www2.whoi.edu/site/amooney/

https://oceanbites.org/coral_phonotaxic/

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I cannot wait to meet with the scientists at The Sensory Ecology and Bioacoustics lab to learn about their research.  

OB Fishing Pier

The other day I went fishing with my friends Aiden and Westley.  My family went out to lunch at the Lookout Tavern in Oak Bluffs and there just so happens to be a fishing pier right across from the restaurant. When we parked next to the restaurant, Aiden and I quickly hopped out of the car and grabbed the three rods each of us brought. We ran to the end of the pier and started to rig up. We brought three rods because we were going to be using mainly bait rigs, so we could set the rods out and leave them. I put some squid on a porgy rig.  After a couple of seconds, I felt a a porgy grab my bait. I let it eat for a few seconds before I set the hook. I reeled him in and quickly released it. The next cast I got another porgy. They were sure hungry. My mom drove up and dropped of Westley, along with all of his fishing gear. After catching about ten porgy, we decided rig up the rest of the rods. One of the of the rods was a 10 foot 6 St Croix surf rod. The longer the rod, the farther you can cast and this rod was was almost 3 feet longer than the rest of our rods. Earlier that day I tied a rig that looks like the one below. The weight is shaped like a pyramid so it travels through the water like a bullet and is great for long distance casting.

So I grabbed the big rod and put the head of a squid on.  There were a few things I could catch with this rig: a dogfish, a big sea bass, a skate or maybe even a nice fluke. I casted it out and left it there. About an hour later, the rod started to shake. I grabbed the rod and waited a few seconds then, started to reel. I was using a circle hook, so I did not need to set the hook. A circle hook is a special type of hook that has a beveled tip that always hooks the fish in the corner of the mouth. It better for the fish and it easier to remove the hook. When I reeled the fish up to the pier, to my delight it was a fluke. I was very excited and happy that I had just caught my first fluke on the Vineyard. Using the pier net we lifted the fish up, took a few photos, and then released it. The fluke was around 18 inches.

While we were fishing for porgy, my friend Aiden also managed to catch a interesting puffer fish.  We do not know what species it is, but here are a few pictures.

The last but not least interesting catch was a striped bass. My friend, Westley, caught it using an entire mackerel. I loved fishing on the pier and cannot wait to go back again.

Uncle Seth's Pond

Today I will cover my adventures at Seth's Pond. Seth's Pond is located on the northern edge of Martha's Vineyard to the west of West Tisbury and is a popular swimming location.  The water in Seth's Pond is crystal clear and relatively cool, which makes it a prime habitat for cooler water species such as trout. Some of the species that inhabit Seth's Pond are: yellow perch, chain pickerel, largemouth bass, bluegill, and the pond is stocked with trout. At the top of the food chain are largemouth bass and chain pickerel. These two fish are quite different and have different ways of getting food. Chain Pickerel like to hide on the edges of beds of weed and wait for unsuspected prey to swim by before they swoop out and grab it with their very sharp teeth. Chain pickerel will eat pretty much anything, from bugs to birds to frogs and even their own species. Largemouth bass on the other hand, have practically no teeth at all and instead they have a very large mouth that they use to swallow their prey whole. They eat similar things like frogs, birds, and smaller fish. In Seth's Pond however the main food source for these two species of fish would primarily be yellow perch along with some bluegill and other small fish species.  This is important to know when selecting a lure.  I chose a Rapala yellow perch lure. This lure perfectly imitates a small yellow perch swimming. Here is a picture of that yellow perch lure alongside an actual yellow perch I caught in Seth's Pond.  

The one on the top is a large mouth bass that weighed around 3 pounds and the one on the bottom is a chain pickerel that was probably a pound or less. I caught both of them by casting into small coves from a kayak in Seth’s Pond.  

 

Day 4: Woodstock, Vermont

Day Four: Fly Fishing

On the final day at Woodstock, we drove to the farm and I did a little fishing.  I caught a few brookies but my mom arranged for me to go fishing with a fly fishing guide. The guide’s name was, Jon.  If you are looking for a great fly fishing guide for a day trip, I would recommend him. Click here to find his website. Jon and I made a plan to go to a river called the Black River first.  Our target was large brown and rainbow trout. After that, we would go to a river called the silver river (sorry it is a secret) and target some brookies and browns. But since we had a ton of time, we decided to try and discover some small brook trout streams on our way to the Black River.  We noticed a tiny stream in a small gulley on the side of the road. There were no buildings, houses, or anything anywhere close to this stream and that's what they need to flourish because they are very sensitive to pollution.  They need clean, cold mountain water. We parked the car on the side of the road and found a way to get down the steep slope. We saw a small waterfall and a large area wear the water pooled up. We first threw a little nymph fly and almost immediately hooked up a small brook trout, my first fish on the fly of the trip. I did not manage to get a photo of this fish. We worked our way up stream and we tied on a dry fly. If you do not know what a dry fly is, it’s a completely weightless fly that floats on the surface and imitates an insect that fell in the water. We casted into this small pool and one brookie hit my fly twice but I did not get him. I was disappointed, but I had just found my love for dry fly fishing.  Some smaller Brook Trout went for the fly but did not hook any of them, so we decided to go to the Black River. We were fishing the Black River but after a little we concluded that the stream was just too warm and the trout would be inactive. We headed to the secret river next. We drove for a little while before we finally arrived the river. It was much smaller than the Black River but still larger than the river at the horse farm. We worked our way up and found this one spot that looked really good. I casted out the fly and let it drift for a few second and all the sudden a nice sized wild brown trout shot up and ate the fly. We tried the rest of the stream and found one deep hole that was full of brook trout, but they did not want to eat anything. We went up a little bit farther up, and I caught another brown on the dry fly. After fishing for almost 12 hours straight, we called it a day.  Overall my trip was amazing. I cannot wait to come back next year when my mom has her horse competition again.

Day 3: Woodstock, Vermont

Day Three: The Brookie Jackpot

Today was my one of my favorite days in Woodstock, Vermont because I caught more than 40 brook trout ranging from an inch all the way up 12 and a half inches. This was the day that I fished this creek from head to toe. I probably walked up and down the entire mile stretch of creek three times throughout the day finding and fishing all of the best spots.

Here is what I have concluded after finding the places that the brook trout like best. They like deeper water. They stay on the bottom, safe from predators, and they like water that is also fast flowing. Often times during the day, the larger brook trout will reside under rocks that have space under them or trees that have grown next to the creek where the soil eroded creating a small almost cave like area for the brook trout to hide in. Now let's talk about what they are eating. Brook trout love spinners because they imitate minnows or baby brook trout, but on the other hand, they also love natural baits such as salamanders and worms. Bait is is better for catching the larger brook trout that hide under rocks because you can drift it with the current of the creek under the large rocks and it is bound to get viciously attacked even by the smallest of brook trout. If there is a deep pool that has lots of shade the brook trout will often come out from under the rocks and face upstream swimming in the current waiting for something to come down stream that they can eat.  When fishing these pools it is best to throw a small spinner and reel it in so it imitates a small fish swimming downstream in the current. Using this technique I caught my two largest brook trout of the trip. When using live bait your hook up ratio is a lot less because there is only one small hook at the front of the bait and you have to wait for the trout to swallow the bait enough so you can actually hook it  If you are looking for quantity over size, I found the perfect technique. Use a hook sized 16-18 with a little piece of worm and a sinker.  You can catch super tiny brook trout and in the mix you will catch a few big ones.  If you are targeting larger brook trout use hooks around the 6 to 8 size.

Day 1 & 2: Fishing in Woodstock, Vermont

Day One: Woodstock, Vermont

My mom loves horseback riding like I love fishing. This weekend there was a dressage competition in Vermont and my mom’s barn on the island always goes to it. Last Wednesday at 5:00 in the morning we drove to the the horse farm, loaded the horses on the trailers, and embarked on our, not so comfortable, six hour drive to Woodstock, Vermont.  

When we got there, it was pouring rain.  I quickly got on my gear and sprinted to the creek with my my fishing rod. I had already put on a tiny panther martin gold spinner because there is a creek that goes straight through the horse farm that is loaded with brook trout. If your wondering what a spinner is it is a type of lure that  imitates a minnow. I walked straight to this place where the water pooled up into a nice deep hole and casted. I reeled in for a couple of seconds and BOOM… A giant brook trout slammed my lure, well at least giant for this size of a creek. I pulled him in, admired his beauty for a few seconds, snapped a few photos, and let him swim away back into the icy cold mountain water.
Next cast, I hooked onto a smaller one but size doesn't matter to me. The beauty of these fish is all I care about. I let him go and took a few more casts. Brook trout are very smart and had figured out that the shiny spinner that imitated a minnow was not real and they best stay away from it. I walked down the stream a little bit until I came to some nice pools with some more brook trout swimming in the current at the bottom. Unfortunately they did not bite, so after about an hour of fishing I started to head back to the spot I started at and had the best luck.   I took a cast and got a smaller one again, but after that they stopped biting. It was time to move on.

My older cousin's husband, Ramone, picked me up and we went to the Connecticut River. The Connecticut River has world class smallmouth bass fishing, so we decided to throw a topwater lure called a bomber to see if we could catch some big ones.  At the end of the day, I ended up only getting one small bass, but at least I didn't get skunked (which means not catching any fish). Normally when Ramone goes to this spot, he catches tons of massive smallies. Since this day was really slow, we decided to call it quits. All and All I was happy that I had caught some beautiful brook trout, which was my only goal of the trip.

Day Two: Woodstock

That night I slept at my Aunt's house and the next day me and Ramone did a little trout fishing.  Unfortunately, my phone was broken and we only ended up not catching one small brook trout. I had about four on, but they all managed to shake the hook off.  Later that day, Ramone and I went back to the Connecticut River and we caught two smaller smallmouth bass that were around two pounds each.

WHOI 2018: Hydrophone

This year I have continued my relationship with WHOI, and have started a very interesting project. My challenge is to build a small hydrophone to listen to sounds underwater and learn more about sound pollution and how it affects marine life.  I am also attempting to connect the hydrophone to a phone so we can collect sound data in different areas in Martha’s Vineyard. 

Once we arrived in Woods Hole Amanda and I met Stacey Strong, the WHOI teacher fellow that we worked with last year on our microplastics project.  She took us to the applied ocean physics and engineering department.  Before we started to construct the Hydrophone, I met with a few other researchers.  

Beckett Colson showed me the new projects he was working on in the Deep Submergence Laboratory and all of the new things going on the lab since I had last been there. Walking into the lab brought back lots of memories from last year, like when we emptied out the bottle of dove body wash to find if their were microplastics in it and all of the different high tech tools they used such as the mining analyzer that looks almost like a radar gun. This year the lab looked completely different, well at least the projects did. Becket has been designing and making a small machine that analyzes carbon levels in certain gasses by using an infrared laser that beams throughout these resin printed tubes that chamber the gas. It is crazy to think that Beckett made this because it almost looks like some high tech movie prop. After walking around the room a bit something caught my eye, there was what looked to be an ROV in the process of being built, and it was not any ordinary ROV.  This ROV was made to go down very deep. 

After leaving the lab, Beckett introduced me to William Pardis, who was working on a small device that could be strapped to drones to measure gases. 

After learning about some really interesting work, we started to build the hydrophone.  To construct the hydrophone we used a video created by an engineer.  This video was created to make it possible for those interested in science projects to build a hand-on, affordable hydrophone. Click here to watch the video.  Click here if you would like the handwritten instructions.  As we were building the hydrophone, I learned a lot of new things such as how to use a soldering gun.

Connecting the hydrophone to our phone was not as easy we expected.  After doing a little bit of research, I figured out that we had the incorrect adaptor.  We needed a microphone to audio adapter because iphone needs a four band audio input and the one we were using is a three band microphone input cable.  When we plugged in our hydrophone, the iphone did not recognize it.  So far we have not been able to get it to work, but we are hopeful that after our new adapter comes in, we will be able to get it to work.  Currently we can hear tapping noises when the hydrophone is plugged into headphones, but when we tested it out in Menemsha Harbor near the bike ferry, we did not pick up any of the sounds.   As Stacey Strong stated, “The key to engineering is being able to embrace the struggle as part of the process.”

           

Fishing in Martha's Vineyard

Since last year I picked up a new hobby, fishing. Fishing with my friends is now by far my favorite past time.  Whenever I have free time, I am fishing.  One of the reasons I like fishing is because I enjoy learning about the diverse species.  All the fish on this blog were released back into their habitat.      

Fishing is a very diverse sport/hobby. You can go sport fishing 60 miles off the coast of the Vineyard for 600 pound tuna or you can take a short and peaceful kayak trip through the many freshwater ponds of the Vineyard catching perch, largemouth bass, trout, and pickerel.

If there's one thing that this blog is lacking is it’s the coverage of fish species on the Vineyard. Martha's Vineyard is known for its world class striped bass and all around saltwater fishing, but few people have covered the amazing freshwater fishing in the Vineyard.  They are so many great freshwater fishing areas on the Vineyard.  Fishing is one of the many things you can do on the Vineyard to experience its beauty, while having lots of fun.

Micro-Organisms

This year we started to collect microorganisms using the plankton net we made for collecting micro-plastics. We collected all of our microorganisms samples at Menemsha Public Beach. I would wade into the water and drag the plankton net behind me.  After I felt like a had enough samples in the net, I would swiftly lift it out of the water making sure nothing could escape while capturing the water in the bottle at the bottom. Then we would carry it up the beach and unscrew the cap above a Tupperware, releasing all of the water with plankton/seaweed into it.  Sometime we would notice lots of organisms in our sample right away.

Other times, we would notice something tiny moving and realize we had found something really interesting.  We took pictures of these organisms and then released them.

We found this organism.

We also found this crab, which looks like it recently left the megalopa stage.  

Next we put some of the water through the PVC sieves we made.  The sieves sorted the microorganisms by size.

We also just collected some of the water in vials to take home. After collecting all of the samples, we went home and started to look at them under a microscope. As soon as I stated to look, I noticed some interesting things.  We took pictures of our slides, but we will need to do more research to figure what we are looking at.  

I also saw lots of zooplankton swimming around but they were so quick, it was hard to focus on them with the microscope.  

I saw a tiny creature that almost looked like a jellyfish, but we wonder if it really is because of how jellyfish develop. See below to learn more about the life cycle.

I need to do a lot more research to fully understand this though.

This is a video of the organism we observed.

We also saw a small worm-like creature.  When we touched it accidentally, it went crazy and wiggled back and forth extremely fast.  You can see two of these organisms in the video below.  

We are not sure what species these organisms are, but we are excited to find out.  If you happen to know or have any background information or any of the organisms we posted, we would love to hear from you.

We have purchased a few books that Suzan Bellincampi, the director of the Felix Neck Wildlife Sanctuary, recommended.  We are going to do some researching this winter.  

Marine Animals of Southern New England and New York

Zooplankton of the Atlantic and Gulf Coasts

Can you guess what we'll be focusing on next summer in Martha’s Vineyard?   I bet you can.