Wednesday 30 January 2013

This summer we are offering two field courses: Download the complete appliaction form and schedule from our webiste www.huntsmanmarine.ca - Education - public programs - summer courses


·         Marine Biology (students 15 to 18 years old)

Monday, July 8 to Friday, July 12



            All-inclusive fee: $610  - if you register before May 8th;  Regular Fee $670

A fun hands-on introduction biology and some local research projects. You will assist with real time baseline data collection for a number of on-going projects and have an opportunity to work alongside Huntsman scientists. The different research techniques and methods that you will learn about should be transferable to your school work. It is not always serious stuff!

You’ll learn about  -
*  invertebrate biodiversity
*  invasive species, such as green crabs and pancake tunicates
*  local coldwater fish species
*  connections between art and biology

 ·         All Things Marine (adults and teachers)

Monday, July 15 to Friday, July 19



All-inclusive fee: $610  - if you register before May 15th;  Regular Fee $670

There is no better maritime outdoor classroom than Canada’s own Bay of Fundy. Twice a day the tide at the mouth of the Bay rise and fall eight meters stirring up nutrients that have drifted to the ocean floor.  Join us as we explore this unique environment and the diversity of life it supports. What we catch and collect is what we will study, draw, print and cook! Time is also set aside to share ideas on how to adapt our marine examples to your own classroom.

Discover:
*  the diversity of local ecosystems and their inhabitants
*  invaders new and old
*  St. Andrews by-the-sea past and present
*  ties to different levels of the science curriculum



The Course Fees cover: 4 night dormitory accommodation, all meals, boat and lab fees, admissions, taxes. You just need to find your way to the Huntsman in St. Andrews!!


Friday 18 January 2013

Lobster life cycle: from larva to adult


From the time a lobster is settled at the bottom of the ocean, he will molt about 25 more times in about 7 to 9 years to grow and become a legal size lobster for the market. And even as small as he is when he settles (he is barely bigger than a dime), he will exhibit all the classic behaviors of adult lobsters, like territorial fights, hunting skills, and housekeeping skills (they are able to pick up and push rocks as big as themselves to re-arrange their living quarters).
Out of the thousands of larvae that can hatch under a female’s tail, only a handful will ever become an adult. So many dangers lurk in the ocean, that young lobsters only have a small chance of survival. As larvae, they are part of plankton eaten by so many shrimps, crabs, mollusks, and even whales. Fish like cod are their number one predator, and many more list the lobster as part of their diet, especially benthic species like flounders, sculpins and wolffishes. But enough of them make it, and today, some say there are still enough lobsters to go around. Since ocean currents dictate where the larvae end up, studies have already started to find the correlation between current behaviors and lobster population cycles. There is still so much more we need to know, and it will take many more years before we fully understand the lobster’s life cycle, regardless of the species.

In the end, lobsters almost take a decade to be considered legal size, and since they start life as tiny individuals with lots of predators, it is amazing to see how they manage to make it so far. The more we learn about them, the more we have an appreciation of their survival skills. They are equipped with two very strong claws, and are able to flee quickly with short backwards swimming bursts as adults, but they remain vulnerable nevertheless, even fearing attacks from other lobsters. The large numbers of eggs laid by females (a 20 lbs female can lay close to 80,000 eggs at once) may explain why the larvae still have a chance to make it, but it is such a long process, that the odds do not seem to be with them. However, the lobster is not without its successful strategies, and it is capable of overcoming many obstacles.
The lobster still has so much more to reveal about its life cycle, but we are now getting a better picture of how they come to be. Plenty of opportunities still exist for new researchers, and this subject will always be a fascinating one for many of us. Hopefully, we will develop a better respect for this wonderful and intriguing creature.

Thursday 17 January 2013

Lobster life cycle: the larvae


Right after hatching, lobsters are considered larvae, and they are so small that they are best viewed using a microscope or a good magnifying lens. They do not resemble an adult lobster, but rather look like a small shrimp. Because they are so small, the ocean currents simply take them away, and it is impossible for the female to care for them. They are basically on their own. They are not alone however, and unfortunately, many other tiny animals eat them. Even baby lobsters can eat each other. They do not make the distinction between a small shrimp and each other, so many of them do not survive the first few days. The larvae go through 3 different stages (each with a molt) in the next 3 or 4 weeks, and each stage shows a small physical change. We start to see some swimmerets (which are the little feathery paddles under the tail) during the second stage, and the tip of the tail develops some uropods (the round pieces of shell that gives the tail a fan shape) at the third stage. At this point, the tiny larvae are still at the mercy of the currents, and they spend the majority of their time in the top layer of the water.

If they survive after that first month of life, they will molt again to become post-larval, otherwise known as the fourth stage. To many biologists who study lobsters, this is the most interesting stage to watch. First of all, the young lobsters finally look more like an adult, complete with 2 larger claws in the front. Second of all, they are much more active and can actually swim around. Picture Superman flying through the air with both arms out, and you will have a good idea how the lobsters swim at this stage. They are nicknamed the “Superlobsters”, as they leap forward through the water at great speeds (for a crustacean) with both claws together, swimming near the surface, sometimes twirling and doing somersaults. This is the only time in their lives when they will swim forward in this fashion. And it only lasts about 10 days.

This stage does allow them to explore new horizons, and near the end of the Superlobster stage, the young ones will descend on the ocean floor to find a proper place to hide. Nurseries, as scientists call them, are areas made of small pebbles on the seafloor, which provide hiding spots barely bigger than the lobsters themselves. A perfect fit is what they need to feel safe, so if the pebbles are too small or too big, they cannot settle. Therefore, the Superlobster stage can last longer if the lobster is unable to find the perfect spot. Once he decides to settle down, he will molt again, and start the rest of his life as a bottom dweller.

Tuesday 15 January 2013

The life cycle of the lobster: the eggs


We are talking about the life cycle of the American lobster. On the last post, we discussed mating, but now, what happens after that? Amazingly enough, the female lobster will hold on to that sperm for about a year before she uses it. That summer, she will fertilize her eggs with it, by laying them under her tail. A berried female is one that shows all of her eggs glued under her tail, looking like thousands of little black berries. Inside each egg is an embryo, and during another 12 months or so, that embryo will develop by actually molting several times inside the egg. In the photo below, we can see the black mass of eggs in between the swimmerets under the tail (abdomen).

In the meantime, the female will hold on to those eggs by keeping her tail curled in, and every now and then she will actually open her tail and fan the eggs with seawater. One can speculate that she is caring for her offspring, but nothing is certain. The eggs do stay attached to her during that time, until they are ready to hatch the following summer. So from the time the lobsters mate, to the time the young lobsters hatch, nearly two years have gone by.