Birds seen offshore:
- Wilson's Storm-petrel, 1.
- Manx Shearwater, 3.
- Northern Gannet, 30.
- Black-bellied Plover, 3.
- Herring Gull, 50.
- Great Black-backed Gull, 30.
- Chimney Swift, 1, about 5 miles off shore.
The marine mammal and fish list, thanks to Krill:
- 1 basking shark
- 4 - 5 harbor porpoise
- 1 humpback whale - Nile
- 3 to 4 minke whales
- 1 finback whale
- PHYTOPLANKTON: dinoflagellate Protoperidinium sp. Many.
- PHYTOPLANKTON: Diatoms. A few.
- COPEPODA: Centropages sp. The predominant organism in our sample.
- COPEPODA: Oithona sp. Fewer than the centropages.
- COPEPODA: nauplii.
- CLADOCERANS: Many.
- LARVAE: Fish eggs. Many. Lots more than we had last October in this area.
Every field trip is valuable, in that each one reveals more of Nature and sheds light on its patterns. This six hour 100-mile round trip benefitted by beautiful sunny weather but there were few whales and almost no seabirds (50 N.Gannets, zero shearwaters and only one individual storm petrel). Unlike many of our other trips in this series, we found no "hot spots" buzzing with high activity. The only area with a few whales was near the southeast end of our journey, and we did one 7-minute plankton tow there at 11:55am, and found a moderate amount of zooplankton and greenish/brownish phytoplankton (mostly dinoflagelates, few diatoms -- unlike last October). More trip details will be added here over the next week...
Here is the chlorophyll concentration map based on MODIS/Aqua satellite photos the day before, on June 10, 2017 around 5pm. Note the relatively low concentrations (no red or orange) off the coast of Massachusetts, compared with the Maine coast (orange and especially red indicates high concentration of chlorophyll-a, required for photosynthesis, and a good indicator of phytoplankton concentrations in these waters). Given these low chlorophyll/plankton concentrations in waters off Massachusetts, we should probably not be surprised that we had few birds and whales...
You can expand your view of this map by clicking on it, and then later pressing the Esc key to return. This map comes from... www.seasurface.umaine.edu/frames_xband.html
which is part of the MODIS data published at UMaine...
This 500ml bottle contains most of the plankton collected at 11:55am June 11, 2017 in a seven minute tow, at about 3knots. Note the many thousands of dots (zooplankton, probably mostly copepods, each around 1mm or less), plus the green/brown color, indicating chlorophyll-a and the presence of phytoplankton, probably diatoms (1/100 to 1/1000 the size of the copepods), to be confirmed by lab analysis in a few weeeks. Noticeably lacking from this plankton tow were any Salps (which prey on phytoplankton), which we regularly collect in these same waters in the Autumn. Click on the image to enlarge it, and then press the Esc key to return...
We need to look at these under a good microscope...
Wayne Petersen studying our good plankton catch:
If we compare the color in this bottle of plankton on June 11, with the color we found last October 22, 2016 in that hot-spot of high activity (see the next post below, and the second of the two bottles shown below), this June 11th bottle is only half as dark, half as green/brown, suggesting less phytoplankton than we had last October in that hot-spot. This is consistent with our emerging theory that whale and seabird concentrations are positively correlated with the density of phytoplankton and its darker shade of green/brown (caused by chlorophyll-a). Note that the plankton net and collection methods were the same for both the October 2016 and the June 2017 plankton tows, so they are comparable...
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| These two bottles are not from June 2017. These two bottles are plankton samples collected in October 2016 from two different parts of Stellwagen Bank: a quiet area with no birds (bottle on left) and a highly active area with whales and seabirds (the bottle on the right). Note that the second bottle is darker than the plankton we collected on June 11th, in a relatively quiet area, with just a few whales, and hardly any seabirds. |
Note that this green/brown color shows on satellite photographs taken from high above the Earth, and gives an indication of where the phytoplankton is "blooming". See the map above, where the green/brown actual colors of the ocean have been transformed into red/orange/yellow, etc.
A review of our plankton sample was done at UConn on June 16th. Compared with our October 2016 sample from the same general area of SW Stellwagen Bank, this June 11 sample had fewer planktonic organisms, which correlates with the low number of seabirds and whales, and may be causal. Unlike October, the phytoplankton were mostly Protoperidinium dinoflagellates, with few diatoms. June had many more fish eggs than we had in October. The predominant organism on June 11 was Centropages copepods, with a smaller number of Oithona copepods. We also had a large number of Cladocerans in June, another microscopic crustacean. Some photos will be inserted here...
The commonest phytoplankton we had on June 11 was the dinoflagellate Protoperidinium, several of which are shown here, with their 3 appendages...
The most numerous zooplankton on June 11 was the copepod called Centropages...
Some of our Naturalists: Prof. Adrian Jordaan (bright blue sweater, sitting, in the back),
Jim Sweeney (green cap), Krill Carson (dark blue cap and red sweater),
Wayne Petersen (eyeglasses, facing Krill)...
