Tag: air bladder

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Nicole Macias, June 10, 2009

NOAA Teacher at Sea
Nicole Macias
Onboard NOAA Vessel Oscar Elton Sette 
 May 31-June 28, 2009 

Mission: Lobster Survey
Geographical area of cruise: Northwestern Hawaiian Islands
Date: June 10, 2009

Here I am holding up a spiny lobster.
Here I am holding up a spiny lobster.

Weather Data from the Bridge 
Location: 23° 37.7’N, 164° 43.005’W
Wind Speed: 10 kts.
Air Temp: 25.6° C

Science and Technology Log 

So the job rotation finally put me into the wet lab where I had a few first hand experiences with the lobsters we have diligently been trying to catch. The first day I was a wet lab assistant and the second day I was a measurer. As mentioned before there are two types of lobsters that we are collecting data on–the spiny and the slipper. For each lobster that is caught we record the sex, the carapace length, and if it is a female we record its pleopod length, the status of her eggs and sperm plate.

There are a couple different ways to determine the sex of a spiny lobster. The first is if their back legs have little pinchers on them then they are female, no pinchers than they are male. The female has a sperm plate on the underside of its head (carapace) right before the tail begins. The male gives sperm to the female who carries it on her sperm plate, when she is ready to reproduce she will begin to scratch the sperm onto the underside of her tail where the eggs are. When we record the status of the sperm plate we must indicate either smooth or rough. Smooth means she has yet to start fertilizing her eggs and rough means she has begun scratching off the sperm. The males have a snail like structure at the base of their hind legs, this is their sperm duct that they release sperm from. The female also has much larger pleopods. The pleopods are like little flippers on the underside of the tail. The female uses her pleopods to hold her eggs. When a female is carrying eggs she is considered berried.

This is a picture of a spiny female lobster that is berried (carrying eggs, they are orange). You can also see the pleopods, which are the black with an outline of white flipper like structure. Above that, between the two legs, is the sperm plate. You can tell that she has begun to scratch the sperm off because of the rough texture.
This is a picture of a spiny female lobster that is berried (carrying eggs, they are orange). You can also see the pleopods, which are the black with an outline of white flipper like structure. Above that, between the two legs, is the sperm plate. You can tell that she has begun to scratch the sperm off because of the rough texture.

It is a little different when distinguishing from the male and female slipper lobsters. The easiest way is to locate on which base of the leg they have a pore. If they have a small clear pore on the bottom leg then they are male. If the pore is on the base of the third leg then they are female. The slipper lobsters have pleopods but they are much smaller than the spiny lobster.

This is a male because of the snail like structures (sperm duct) at the base of his legs.
This is a male because of the snail like structures (sperm duct) at the base of his legs.

The job of the pleopods is to hold the eggs before and after fertilization. The reason that their length is recorded is so that it can be compared to its body length to determine maturity. Even though this seems like a lot of information once you get the hang of the process it goes by very quickly. For every lobster that we catch we must determine whether it has a tag form the previous years. If it does then we have to make sure we put it back at the same location we found it. We are not tagging any lobsters on this cruise. I do not know why so that is something that I will have to figure out and report back to you on. On the next log I will talk about the life stages of a lobster! 

This is a picture of the top half of a spiny lobster. The carapace is the section between the eyes all the way to where the head ends and the tail starts.
This is a picture of the top half of a spiny lobster. The carapace is the section between the eyes all the way to where the head ends and the tail starts.

Personal Log 

I am definitely ready for a day off. Being a research technician is a lot more work than I was expecting. It is a lot of quick intensive manual labor followed by a lot of waiting until the next burst of work. I am beginning to despise the smell of rotting mackerel blood. It seems to follow me wherever I go on the boat. I am looking forward to the two-day transit to our next stop, Maro Reef, even though it is not for another four days. At least I am eating well and trying to fit in a work out every day.

I cannot wait to come home and tell everyone about my experiences in person.

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Nicole Macias, June 4, 2009

NOAA Teacher at Sea
Nicole Macias
Onboard NOAA Vessel Oscar Elton Sette 
 May 31-June 28, 2009 

Mission: Lobster Survey
Geographical area of cruise: Northwestern Hawaiian Islands
Date: June 4, 2009

Weather Data from the Bridge 
Location: 23° 15.7’N, 164° 26.7’W
Wind Speed: 8kts.
Wave Height: 1 ft.
Swell Wave Height: 3-4 ft.
Water Temp: 26.3 ° C
Air Temp: 28° C

A fish that has its air bladder protruding from its gills.
A fish that has its air bladder protruding from its gills.

Science and Technology Log 

Today was our second full day of hauling and setting the traps. The science team is on a rotating schedule so that everyone gets a chance to work each position. Yesterday, I was a “runner”. My job was to stand in the pit next to the “crackers”. The crackers would take out the specimens and place them in a bucket and then take out the old bait and replace it with new bait. Once the pod was ready to go I would run the bucket to the lab and the pod (trap) down the pit tables to the stackers. It was a labor-intensive job, but at least I was able to see everything that came up in the trap. We did not catch many lobsters, but we did trap quite a few white tip reef sharks. Even though they are not very large they are extremely strong. I would know because I got to throw one over the side of the ship!

This is me in the pit when I was a "runner." So far we are catching more white tip reef sharks than we are lobsters. See the white tip on the shark’s tail fin?
This is me in the pit when I was a “runner.” So far we are catching more white tip reef sharks than we are lobsters. See the white tip on the shark’s tail fin?

Today I was a “stacker.” My job was to take the pods from the runner and stack them on the fantail, the back of the boat where the traps are released later in the day. The pods are stacked 4 high and end up covering the entire back of the boat. There are 160 pods all together. We release 10 strings of 8 pods each and 4 strings with 20 pods each. The main focus of the research being conducted is to collect data on the population of lobsters in the North West Hawaiian Islands. Even though we are targeting lobsters we record the data on everything we catch. Anything beside lobsters are considered by-catch. By-catch is considered anything that is caught accidentally. We are setting these traps for lobsters, but many times other animals will work there way into the pods. This is unfortunate for any fish that gets caught in the traps because they are pulled to the surface so fast that their air bladder expands causing a balloon-like structure to protrude from their mouth.

This is the feeding frenzy that follows the ship until the end of the day when we give them all our old bait. They are Galapagos Reef Sharks.
This is the feeding frenzy that follows the ship until the end of the day when we give them all our old bait. They are Galapagos Reef Sharks.

This “balloon” enables them to swim down and they end up being eaten by a predator or drowning. In a normal situation the swim bladder helps a fish regulate their buoyancy. The by-catch problem is seen in many commercial fishing industries. Usually they are dealing with a larger quantity of equipment and in certain instances, such as long lining, many sharks and turtles end up dying unnecessarily. The two main species of lobsters that are found in Hawaiian waters are the spiny lobster, Panulirus marginatus, and slipper lobsters, Scyllarides squammosus. Both species are also found in the waters off South Florida, but they do look a little different. The lobsters in Hawaii have more of a purple color to them. I have not come into much contact with them since my day in the lab isn’t for a while in the rotation. Once I am in the lab I will be able to report back with more information about them. Tomorrow I am a stacker again, so my biceps will be getting really big. I do know that on the first day we only caught 3 spiny lobsters and on the second day 21.

Oh! The most exciting part of the day is after we have finished hauling all the traps and replacing the old bait with new bait, we dump the old bait overboard and there is a feeding frenzy amongst the resident Galapagos sharks that follow our boat.

Personal Log 

Here I am on the fantail of the deck scrubbing the mackrel blood after setting 180 traps.
Here I am on the fantail of the deck scrubbing the mackrel blood after setting 180 traps.

Well my feet are very sore from being wet and in shoes all day. They are definitely not used to being in closed toed shoes everyday. I am ready to start working in the lab and learning more scientific information than just performing physical labor. With all the energy I am exerting I am definitely replacing all the lost energy with the delicious food that is different and amazing everyday. Today we had Hawaiian cornbread with pineapple. It was out of this world! We have also been eating a lot of fresh fish since one of the rotations included bottom fishing. I have yet to be in this rotation.

I am beginning to make friends with everyone on the ship. I am sure by the end of the month I will have forged some great friendships. It does seem like I have been on the ship for quite some time. I hope the days start going by a little faster. I am beginning to miss Florida!

I will be writing soon. Hopefully with some exciting adventures!