Category: Geoff Goodenow

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Geoff Goodenow, May 19, 2004

NOAA Teacher at Sea
Geoff Goodenow
Onboard NOAA Ship Oscar Elton Sette
May 2 – 25, 2004

Mission: Swordfish Assessment Survey
Geographical Area: Hawaiian Islands
Date: May 19, 2004

Time: 1615

Lat: 19 15 N
Long: 157 14 W
Sky: Cloudy all day with light to moderate rain showers throughout the day after longline retrieval. Ended by supper time, but the sky remained overcast.

Air temp: 23.6 C
Barometer: 1012.5
Wind: 106 degrees 16 at knots
Relative humidity: 73.4%
Sea temp: 26.2 C
Depth: 3959.8 m
Sea: Swells less than a meter.

Science and Technology Log

Not a big catch today, but everything we did catch came at once resulting in a flurry of activity for a short time. A blue shark was kept, and our largest swordfish so far came up dead. Too bad as it would have been an excellent one to tag.

For today’s in depth science report, I will refer to a couple of papers both coauthored by our chief scientist, Rich, relating to vertical movements of some of the species we have seen. Some fish tend to stay within particular vertical realms while others traverse them. What factors influence the animals’ movements?

One seems to be temperature. In a study of yellowfin tuna, blue marlin and striped marlins, all three were found to descend to depths where water is no more than 8C below surface temperature. Where oxygen levels in the water are not a factor, all three of these species seem to be restricted by the effects of water temperature on cardiac muscle function.

Bigeye tuna as you will recall stay deep (500m) by day and rise to the surface waters at night. At depth the animals are exposing themselves to ambient temperatures that are up to 20C colder and oxygen levels much lower than in the upper layers. Swordfish and bigeye thresher sharks exhibit patterns similar to those of the bigeye tuna.

What about those heat exchange mechanisms described in earlier issues of my log? Shouldn’t they, if present, allow a fish to tolerate a wide temperature range? While indeed they are present in some species, they are not working to keep blood warm as it goes to and through the heart. Any heat left in the blood on its return to the heart is lost as it passes through the gills. Since the heart is “downstream” of the gills, cardiac muscle remains within 1C of ambient temp. Studies show that temp. reductions cause heart rate and output to decrease.

Yellowfin tuna and the marlins seem to have no ability to increase heart rate or cardiac output following sudden temperature reductions. Consequently, they stay within that 8C window of surface temp.

So how do the bigeye tunas and others manage to negotiate these temperature realms with apparent ease? The question remains, the full story unknown so untold. Perhaps by the time you are here as a teacher at sea you can fill us in with the details. I’ll be waiting!

I’ll complete this look at physiology tomorrow with a bit more to relay about the oxygen issue.

Goodenow 5-19-04 bite marks
This was taken to show countershading and nuptial bites. The large bite is obvious but also note the smaller teeth marks below. The bites are made by the males on the females.

Personal Log

I usually have a good start on the log by supper time but not today. In the quiet following the period of intense longline activity, I began the process of securing the jaws of the blue shark for display. This was a female of good size (165cm, 45kg) and with a nice set of choppers. I was being pelted with rain as I worked through lunch and beyond. I thought if I stopped I wouldn’t go back out to deal with it any more so I just kept peeling away the flesh to expose the teeth and reduce future odor issues. Had it pretty well done as chill started to get to me. I headed for the warmth of a stairwell over the engine room pausing momentarily to enjoy the (usually) stifling heat before finishing my route to room and warm shower. I did return to inspect my work. In comparing it to Eva’s similar effort I felt more had to be done to match her high standard. But now it’s done and jaws are held wide apart with crossed chopsticks as nature tends to the final phase.

No longline duties at the start of tonight’s set which I think is in last night’s neighborhood. Perhaps I will be in there as a reliever a bit later.

Question:

For something completely different and to address the history buffs among you:

How long ago is it estimated that Polynesians discovered and settled in the Hawaiian Islands?   When were the islands discovered by European explorers? Why was captain Cook first welcomed by the native people, but not received so well (and eventually killed) when he returned shortly after his departure?

Any subject areas I’ve not touched on yet?

Geoff

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Geoff Goodenow, May 17, 2004

NOAA Teacher at Sea
Geoff Goodenow
Onboard NOAA Ship Oscar Elton Sette
May 2 – 25, 2004

Mission: Swordfish Assessment Survey
Geographical Area: Hawaiian Islands
Date: May 17, 2004

Time: 1600

Lat: 18 24 N
Long: 157 47 W
Sky: Stratus cloud layer shielded us from the sun until longline was in then it started to break up by 1030. Sun for awhile then clouded over again by midafternoon. Thinning by evening but still a good blanket on us.

Air temp: 27.3 C
Barometer: 1011.24
Wind: 35 degrees at 7 knots
Relative humidity: 54.5%
Sea temp: 26.8 C
Depth: 4489.2 m

Sea: 2-3 foot swells; no problems

Science and Technical Log

Yesterday after picking up the line we began a westward passage toward Swordfish Seamount. It was a long way off and there was no hope of getting there last night. The line was set along our course at 18 34 N and 156 47 W at no particular oceanographic feature that I am aware of. Perhaps that is why out haul today was none too exciting — a couple escolar, a snake mackeral and two blue sharks. Only one of the blues was brought on board. We will be at Swordfish to set tonight and look forward to a more interesting catch tomorrow.

I have covered each of the areas of research going on by the science teams aboard for this cruise. Today, my focus will be on sharks. We have caught 4 species so far and that has aroused my interest in these animals. I’ll provide some general info as well as some specifics for the species we have caught. For those of you interested in more, my information comes from two sources: Smiths’ Sea Fishes by Margaret Smith and Phillip Heemstra, and Diversity of Life by E.O. Wilson.

Sharks along with skates and rays are among 700-800 species in the subclass Elasmobranchii of the Class Chondrichthyes. Like all members of the class, their skeletons are entirely cartilaginous, but Elasmobranchs are distinguished by an upper jaw that is not fused to the skull and 5-7 pairs of gill slits.

There are about 350 species of sharks ranging in adult size from the 23 cm green lanternshark to whale sharks, the largest of all fishes, which reach 13 meters. Sharks lack a swim bladder, but produce large amounts of lipids which are stored as oils in the liver for buoyancy. The liver can account for up to 25% of the animal’s total weight. Sharks maintain osmotic (water) balance by maintaining a high concentration of urea (so high as to be deadly to most fishes) in their blood and tissues thereby reducing water loss to their salty environment.

All sharks we have caught (except the bigeye thresher, Order Lamniform) belong to the Order Carchariniform. This is the largest group of sharks; it includes about 200 species. These two orders are distinguished from one another in the following ways:

Carchariniforms: purse-like egg cases or live bearing; a movable nictitating membrane (eye covering).

Lamniforms: bear live young with uterine cannibalism (now there’s an interesting bit) evident in some; no movable nictitating membrane. There are also differences between the orders in the internal structure of their intestines — very interesting but I won’t go into description.

Specifics about each species of shark we have taken follow.

Blue sharks: the most fecund of all sharks; viviparous and bear 35-135 pups per litter; 50 cm at birth; attain 3.5 m; widespread in all oceans; favor water 12-16 C.

Oceanic white tip: in all oceans; away from continental shelves; viviparous bearing 6-8 pups usually; 60-65 cm at birth; up to 3 m; abundant in tropical seas.

Silky: widespread, prefer warm water; feeds inshore and in deep water; viviparous bearing 9-14 pups; 80-85 cm at birth; up to 3 m.

Bigeye thresher: widespread in warm ocean waters; ovoviviporous (provides embyo with no nourishment beyond the original yolk); 2 pups per litter; 100-130 cm at birth; attain 4.5 meters.

Personal Log

Well, I guess you can tell what I did today, and I might have a few more tidbits about sharks to add tomorrow. I am completing the log before the line set tonight so as to take in a movie afterwards. Don’t know what’s playing tonight, but it will be free and relaxing.

Tomorrow begins our last week at sea. Little time remains for you to file your questions with me. I’m looking too for suggestions for topics to try to address so if you have ideas, please suggest. I have asked for a tour of the engine room which is a possibility for Tuesday if tickets aren’t sold out. That might give me some interesting goodies to pass along.

Question:

We have seen fish that are rather uniformly dark in color and some that are brightly colored. What are some of the roles of coloration in fishes (as well as other animals)? Describe countershading and how it serves an animal like the blue shark.

Geoff

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Geoff Goodenow, May 16, 2004

NOAA Teacher at Sea
Geoff Goodenow
Onboard NOAA Ship Oscar Elton Sette
May 2 – 25, 2004

Mission: Swordfish Assessment Survey
Geographical Area: Hawaiian Islands
Date: May 16, 2004

Time: 1615

Lat: 18 25 N
Long: 156 13 W
Sky: A dreary morning with gray stratus clouds all around and an occasional misting of precipitation. Much brighter sky by 1300 — enough to cast shadows, but remained mostly cloudy throughout the day. A pleasent evening with clearing skies.

Air temp: 25.7 C
Barometer: 1011.61
Wind: 352 degrees at 13 knots
Relative humidity: 71.5%
Sea temp: 26.4 C
Depth: 5012.1 m
Sea: 2-3 foot swells

Scientific and Technical Log

Longline retrieval started on a bad note this morning as the line went under the ship. It caused only a short delay as maneuvers were quickly and successfully made to keep it out of the propellers. We brought up an escolar, 2 snake mackeral, and a broadbill swordfish head. A large, angry silky shark came in also. The shark was released after being tagged and “kindly” relinquishing a remora. And finally, a new species for the record, a lancetfish (Alepisaurus ferox). These guys look much like the snake mackeral, a long thin body up to 200cm, nearly cylindrical with a tall uneven dorsal fin (sail)standing perhaps 5 body widths high over nearly 2/3 of its back. The snake mackeral’s dorsal fin does not rise nearly so much. The lancet’s skin was very smooth, scaleless in fact, iridescent and rather pale. They have narrow snout with long sharp teeth.

For those interested in the studies of pelagic fishes, the Pelagic Fisheries Research Program (PFRP) publishes a newsletter which can be viewed online (I think) at http://wwwsoest.hawaii.edu/PFRP . For more on the eye work being done by Kerstin and others see Vol. 6 Number 3 (July-September 2001).

Other studies aboard the SETTE:

Melissa is a master’s program student at Virginia Institute of Marine Sciences (VIMS). She did her undergraduate study at UC San Diego. She has been collecting remoras, larvae from our plankton tows and stomach contents from some fishes, and fin clips from sharks. Here’s what it’s all about:

The remoras are being collected as a favor for her labmate’s work at VIMS. That person is looking at the phylogenetics of remoras and also that of their hosts which include sharks, billfishes, and the occasional baitfish or float. She is also collecting fin clippings from sharks of the genus Carcharhinus (e.g. oceanic white tips, silky sharks) for another labmate working on the sandbar sharks (also in the Carcharhinus genus) off of Virginia, looking at natal homing patterns.

From the plankton tows, Melissa is interested in larvae of the fish family Scombridae which incldes tunas, wahoo, bonitos, and mackeral. Can we find ways to identify them based on their genetics? Samples from all will be sequenced using their mitochondrial DNA in an attempt to find unique interspecific (between species) genetic markers. The value of this is that it would allow easier identification of larval types than does morphological identification. We might more readily then identify where and when particular species spawn and thereby attain a better understanding of their life histories. Are the genetics of a species uniform throughout the range of the fish? If there are significant genetic differences in populations then perhaps it is wise to manage fisheries of that species by area as opposed to globally (one size fits all approach) so as to preserve gene pool diversity. Answers to these questions could lead to management practices that better protect these resources.

This work also has applications in forensic studies. Fish that have been taken illegally and already filleted can be identified by genetic markers enabling better enforcement of regulations. Also, morphological identification of degraded tissue, as in stomach contents where enzymes have done their deed, is impossible.  Stomach contents collected here will be screened using genetic markers for the tuna larvae to see if the larvae are part of that particular fish’s diet.  Applications from this work could potentially aid studies of trophic levels and predator/prey relationships.

Goodenow 5-16-04 shark on cradle
Shark being lifted aboard

Personal Log

Suffered my first injury in shark wrestling today with a slight abrasion to left knee — not enough to scare me away from the next match. Nothing too news worthy to report about the day. It was a rather slow day. Not much sun, humidity was above the norm — a bit uncomfortable outside. Continued reading Wilson’s book, did wash and stewards offered a linen change today which I took advantage of.

There was a moment of excitement this afternoon when a marlin took off with a troll line. It was out of control and our two champion fisherman couldn’t handle it. Gears were stripped in the reel which actually smoked from the heat generated as line spinned off. That rod is out of action for the duration; the fish won that round.

This evening our electronics technician, John, gave me a pictorial introduction to other research cruises of the SETTE which I will share with you another time. And, relieved of longline duties tonight, I spoke with Mike and science in general and some specific regarding his work in fisheries research.

To all of my ’02-’03 Advanced Biology students, I am sorry to report that I was not able to make use of my Secchi disk nor did I even see one on the ship.

Question:

What does the term upwelling mean? Identify several general locations in the oceans where upwelling occurs. What is the biological impact of upwelling in those areas?

Geoff

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Geoff Goodenow, May 15, 2004

NOAA Teacher at Sea
Geoff Goodenow
Onboard NOAA Ship Oscar Elton Sette
May 2 – 25, 2004

Mission: Swordfish Assessment Survey
Geographical Area: Hawaiian Islands
Date: May 15, 2004

Time: 1550

Lat: 18 52 N
Long: 155 47 W
Sky: Bright and sunny over us but the island has a layer of stratus obscuring views to top
Air temp: 26.3 C
Barometer: 1012.72
Wind: 202 degrees at 12 knots
Relative humidity: 62.4
Sea temp: 26.2 C
Depth: 2015.4 m

Sea: Rolling along with 2-3 foot swells; no big deal.

Scientific and Technical Log

Scientific name for the pomfret we caught yesterday is Brama brama and for the silky shark (caught a week or so ago) it is Carcharhinus falciformis.

Today as we trolled just off the Hawaii shoreline as we steamed south to our longline set position. Mike and Chris teamed up again to land a shortbilled spearfish (Tetraturus angustirostris) 161 cm and 17 kg, silvery body with a deep blue dorsal fin — beautiful fish. This one was kept for eye studies and other tissue samples. We pulled a nearly intact fish about 20 cm long from its stomach. The 2 man team of Chris and Mike is working smoothly and efficiently; no fish has a chance against them now.

We will set the longline tonight southeast of the southern tip of Hawaii at Apuupuu Seamount, 929 m below. (18 31N, 155.24 W). Following the set we will be doing a plankton tow.

Vision (one more time):

Another aspect of the vision studies is trying to assess the animal’s speed of vision. Electroretinography measures the response of an eye to light pulses from a flickering source. So called flicker fusion (FF) is reached when the eye loses its ability to perceive individual pulses of light. A relatively high FF value is characteristic of shallow living species compared to deeper dwellers. In the dim light the speed of light gathering is slowed similar to the need to slow a camera’s shutter speed to gather sufficient light.

In concluding this abbreviated look at the vision studies, I’ll try to draw some of the pieces together. Pop up tags show where these animals spend their time in terms of depth, light and temperature realms. We can tell how sensitive an eye is to light and how fast it works. As you will recall, some of these fishes deep dwelling fishes have heat a exchange system located in the eye which keep it warm. It has been shown that speed of vision is affected by temperature change — a warm (above ambient) eye functions more effectively. Much more goes on, but perhaps you get a sense of how different areas of study contribute to a better picture of this function in these pelagic fishes.

To other (non-vision) studies tomorrow.

Personal Log

We steamed toward Kona through the night so that we could ferry Steven to shore and flights to other places. It was great to have met him; I’m sorry he had to jump ship. I got up at 5:30 to experience sunrise (around 6 o’clock). I thought it would be nice to see it rise over the island, but didn’t count on the clouds hanging over the mountains to obscure anything that might have been spectacular; it wasn’t even good from our perspective. But it was nice to see a color that I haven’t seen (except as a flash) in over a week — green. We have been wrapped in a beautiful blue and white world (which I am sure would excite fans of the Penn State Nittany Lions and the Mifflinburg HS Wildcats), but I tend to favor green fields and forests in the mix.

Unfortunately, we didn’t get to touch the green or for that matter the briny deep as snorkeling was denied us. So it was a day of leisure on board. I spent time reading (Diversity of Life), making some journal entries and enjoying the sight of land — perhaps the last for another 9 days (not complaining). I tried to ignore the typical signatures of human presence at Kona: autos, the Big K-Mart and Lowes perched to give exiting customers a grand view across the sea, a cruise ship at anchor, shore front hotels and homes dotting the mountainside. I directed my focus on the crashing surf, blankets of exposed black lava rock interrupting the predominant green, and shear black cliffs dropping to the sea — the natural stuff. It got better the further south we moved along the coast.

Dan guided Kylie and me through filleting of the spearfish this afternoon. Between the three of us (and the catch team, of course) we secured a good bit of food for the crew. This evening I split spool duty with Kerstin then took a chair from which to watch the rest of the set, read and talk with super fisherman Chris.

It’s a great night back in the world of blue and white.

Question:

Can you find the point on the sea where you would be most distant in any direction from land?

Posted on

Geoff Goodenow, May 14, 2004

NOAA Teacher at Sea
Geoff Goodenow
Onboard NOAA Ship Oscar Elton Sette
May 2 – 25, 2004

Mission: Swordfish Assessment Survey
Geographical Area: Hawaiian Islands
Date: May 14, 2004

Time: 1600

Lat: 18 40 N
Long: 158 14 W
Sky: Sunnny with widely scattered cumulus
Air temp: 26.4 C
Barometer: 1011.26
Wind: 172 degrees at 12 knots
Relative humidity: 61.4%
Sea temp: 26.4 C
Depth: 888.5 m

Sea: A few white caps out there; swells in 1-3 foot range — easy going today.

Science and Technology Log

A fairly exciting morning on the longline. Several escolar, a barracuda, and a pomfret (a laterally flattened fish about 30cm long but only 2-3 cm in width with a fine set of sharp teeth). Samples taken from all. We also had a blue shark from which samples were taken and an oceanic white tip shark which was tagged and released. I got to wrestle both. Picked up a few remoras from the sharks. We think we have at least two species of remoras.

This afternoon we passed over Cross Seamount and traversed it several times as we trolled but to no avail. There will be no longline set tonight since we have a date in Kona to drop off one of the current scientific party.

I want to fill in with more of the vision story this evening if I can stay coherent long enough to convey it sensibly. I will touch on the work of Steven, Kerstin, and Rickard.

I have been collecting samples of fish lenses. They vary in size, as you would expect, among different sized fishes. What makes the lenses different from those of most vertebrates is that they are spherical rather than oval in cross section. The cornea of fish is also optically non-functional. Since it has the same refractive index as water, focusing is done by moving the lens back and forth in the eye rather than by changing the shape of the lens as our eye muscles do.

Steven uses laser light to determine the focal point for different colors of light. He suspends lenses in a fluid medium then turns on a laser beam that makes two vertical passes through the diameter of the lens. You can watch light’s path change as the beam migrates. Computer analysis then determines focal point.

Kerstin and Rickard must have live cells from the retina for their studies. Among other things, they are looking at the sensitivity of these cells to different light intensities. Live retina cells convert light to electrical signals which travel via the optical nerve to the brain to produce an image. By attaching electrodes to tissue samples about 1 cm square in size and subjecting the cells to different intensities of light electrical responses of different strengths can be detected and measured. They appear as a wave pattern on a screen. As light intensity is increased, the amplitude of the wave pattern increases. So a flat line (no response) becomes one with small amplitude waves which grow as light intensity increases to a point where more light produces no greater effect.

Lets compare two species, mahi mahi, which stay nearer well lit surface and bigeye tuna which like deeper environs. Which eye would you expect to be more light sensitive? The bigeye. Their cells are stimulated by much lower intensities of light than the mahi’s. They (bigeye) have to be able to detect their prey under minimal light conditions and need the more sensitive eye to do that. Big eyes, big pupils (fish pupil size is fixed) and a “super” sensitive set of retinal cells are adaptations of these fish to their deep environment.

I’ve had enough (as I suppose you have too). I will wrap up the vision story tomorrow or Sunday.

Personal Log

We are headed for Kona. Although we probably will not get any shore time, it has been suggested that there might be an excursion to a place where we can swim/snorkel for awhile. I am hoping very much this it true as are others. A plunge into this element (I guess I should say compound) that we have bobbed around on top of for the past 13 days would be a pleasant change in the routine and scenery.

Reading E.O. Wilson’s The Diversity of Life.

I would like to thank, Ron, a fellow teacher from Michigan who I have never met, for writing a note to tell me that he has been enjoying the logs and also to pose a question. Much appreciated!

Questions:

Sunrise here today is at 6AM and the great yellow ball sets here at 7PM. What time is it rising and setting in your area at this time of year? Find out sunrise and sunset times for the solstices for Honolulu and your area. From that determine A) how much longer the sun is above the horizon for each place in summer vs winter B) which place, Honolulu or your home has more sun time at each solstice? If you find that there are differences explain why they exist.

Geoff