Cold water, big tides

After a very cold night, there was a layer of ice on Pedder Bay again this morning which allowed for some interesting observations and data collection by marine scientists.

Data below were collected by second year Marine Science students at two different times of the morning.

	8:05	am	11:00	am
Depth (m)	Temp (oC)	Salinity (ppt)	Temp (oC)	Salinity (ppt)
0	3.7	28.4	4.6	25.9
0.5	5.8	29.3	5.8	30.1
1.0	6.4	30.3	6.7	30.6
2.0	6.7	30.6	6.7	30.7
3.0	6.7	30.7	6.8	30.8
4.0	6.8	30.7	6.9	30.8
5.0	6.8	30.7	6.9	30.8

One major conclusion can be drawn:

The water is COLD (right down to 5 m where we usually measure temperatures around 10^oC). It is so cold that students’ tongues are turning blue:

Wait a minute… the cold is not the reason for the blue tongues in these Biology students!

We are also experiencing big tides these days (2.8 m tidal range). High tides in the early afternoon:

D block 13:15 11 Jan 2017

F block 9:45 12 Jan 2017

G block 11:00 12 Jan 2017

Tomma touching the top of the piling

Then low tides at night:

Emilio, Heather & Millie at low tide (20:15 11 Jan 2017)

Interesting times!

Pedder Bay pancakes

Pancake ICE, that is!

Pancake ice by Second Nature

Pancake ice under ramp

Defined in a sea ice glossary as “Predominantly circular pieces of ice from 30 centimeters to 3 meters in diameter, and up to about 10 centimeters in thickness with raised rims due to pieces striking against one another. It may be formed on a slight swell from grease ice, shuga, or slush or as a result of the breaking of ice rind, nilas, or under severe conditions of swell or waves, of gray ice.”

Pancake ice is not common in Pedder Bay, but due to many days of cold air temperatures, it is abundant around the Pearson College dock and around the Pedder Bay Marina.

I did a quick measurement of surface salinity (ppt) and seawater temperature (oC):

Yikes!! The poor mergansers, their feet must be very cold!

Snow and Sunrise – 6 December 2016

After a snowfall last night, a stunning sunrise this morning.

Pedder Bay Marina

Pearson College dock

First year Marine Science students also measured seawater temperature and salinity at 9:40 am while the air temperature was 4.2^oC.

Depth (m)	Temp (oC)	Salinity (ppt)
0.0	7.1	18.0
0.5	9.7	29.7
1.0	9.8	30.0
2.0	9.8	30.0

Brrr….

Wonderful Witty’s

Last week as their penultimate field trip, second year Marine Science students explored Witty’s Lagoon as an example of an estuary. We measured water temperature, salinity, and dissolved oxygen at six locations along the estuary. The photo above shows Michael reading out the data that he and Michał collected (seen in the photo below) on Wednesday 13 April.

Noëmi and Kevin collected similar data from the same location (‘Log lake’) on the previous day (Tuesday 12 April 2016).

In the photo below, Tamara & Laura collect data from the ‘ocean’ site.

Data for all three days shown below:

The site that we named ‘Skunk cabbage creek’ was very near this beautiful plant.

We also explored the salt marsh and some of its inhabitants – for several students the plants were cool the spiders were not!

We also found some wonderful invertebrates, both in the estuary and on the sandy beach.

Molting green shore crab

Connor and an asian mudflat snail

Purple ribbon worm

Lugworm poop

Lugworm proper

Temperature & Salinity 13 Nov 2015

Depth (m)	Temp (oC)	Salinity (ppt)
0	10.5	10.4
0.5	9.9	29.4
1.0	9.8	30.4
2.0	9.8	30.7
3.0	9.8	30.7
4.0	9.8	30.7
5.0	9.8	30.8

10:00 am         Pearson College dock

Secchi depth = 1.01 m      Air temp = 15.8^oC

Sea urchin fertilization & development

In second year Biology we are currently studying reproduction and although our focus is human reproduction, sea urchins are a wonderful model to study. Pearson College divers collected about 40 purple sea urchins (Strongylocentrotus purpuratus) and brought them back to the floating lab. In Biology class we injected them with potassium chloride which causes them to release their eggs or sperm.

I have done this lab many times and in many locations and I am very pleased to say that this time was my most successful! The first urchin I injected released many healthy eggs. This is where my luck usually changes because without sperm, eggs are useless. I asked students to choose a male urchin (there is no way to tell by looking at them, so it takes some luck). Bader chose one and very soon after being injected streams of sperm came out of the gonopores!!

Students then took a sample of eggs to look at under the microscope then added sperm in order to watch fertilization.

Photo above at 2 hours post-fertilization. All of the eggs are fertilized and a few are at the two-cell stage.

At 5 hours post-fertilization, there are some two-cell stage embryos but most are at the four-cell stage.

At 10 hours, we had blastulae with big cells, still in their fertilization membranes.

At 21 hours, blastulae with smaller cells, still in their fertilization membranes.

At 26 hours, some of the blastulae hatched out of their membranes and started spinning.

At 6 and 7 days post-fertilization, we had pluteus larvae!

All of the urchin larvae have now been released into Pedder Bay with warm wishes for a long kelp-ful life!

See https://www.flickr.com/photos/130038530@N07/sets/72157651009889142/ for more photos.

Harbour seal necropsy 2014

On Saturday 13 September, many students observed or got directly involved in the necropsy of the little female harbour seal (Phoca vitulina) that we found in the mudflats last week.

With permission from Fisheries and Oceans Canada, we examined the body of the seal inside and out…

Two students, Haruna & Mariam, carefully teased apart the small intestine, stretched it out and measured it to be 12.8 m long.  All that intestine in a seal that was only 0.82 m long!

We did examine many organs but could not determine the cause of death.

 

A very unique opportunity for many Pearson College students! Thanks to all involved including the many photographers.

This is one of my favourite photos from the event… the lens from one of the eyes, which you may be able to see has inverted the image behind it.

Marine science learning adventures at Pearson College

Marine Science students aboard MV Second Nature, head out to Race Rocks Marine Protected Areas to do a quantitative, rocky shore study.

Tidal currents boil and swirl around the study site and safety is the top priority. A sharp look out for sneaker waves keeps everyone dry.

The first job is to stretch out a reference tape measure.

Using ancient but precise, Egyptian technology, the students carefully measure vertical height using a water level and record the abundance of different species as they work their way up the shore.

The students are learning about marine ecology by doing it.

Getting up close and personal with limpets and periwinkles is the best way to make observations.

Direct observations help the students understand broader topics in marine science.

These little brooding anemones may not have a brain but they are sensible enough to “hang on” to their offspring and give them a head start over their ‘cousins’ with planktonic larvae.

These ancient mollusks haven’t changed much in several hundred millions years. That is because they are well adapted to hang on to the rock and scrape off the algae using a metal scraper (aka a radula with iron in it).

These little aggregation anemones host algae in their skin, akin to the corals but soft.

Students work together to try and figure out the biotic and abiotic interactions that are shaping the the distribution of organisms.

Measurements of mussels and barnacles helps make sense of the abundance data.

Now comes the hard part of processing the raw data, pooling data and making sense out of the findings.

Field Season in Full Swing for Marine Scientists at Pearson College

Measuring marine biodiversity is the task today. Teamwork prevails. Many countries, cultures and languages unite to get a handle on species richness and the distribution of individuals across taxa.

Primary productivity experiment

Second year Marine Science students in C block chose to investigate the effect of colour of light on primary productivity in bull kelp (Nereocystis luetkeana). After wrapping five BOD bottles in each of five colours of cellophane plus five bottles in transparent cellophane and including five black bottles, students filled BOD bottles with seawater and one piece (4 cm x 4 cm) of bull kelp.

They measured dissolved oxygen in each bottle:

then left the bottles on the window sill of the floating lab for 4 to 6 hours:

Then they measured dissolved oxygen again:

The data collected are shown below:

And I have to include this photo of the wall by the stairs in the floating lab taken when students were measuring final oxygen levels: