Tuesday 28 July 2009

Portuguese Man o' War!


Living by the coast and spending so much time on, in or by the sea you always imagine that any day soon something formidable, unusual or iconic will wash up on your shores or swim before your very eyes. Well for me today was not that day but for my daughter & husband it was! They were down by the Quay on the Avon estuary when they saw what looked like a small inflated balloon floating past. They immediately recognised it as a Portuguese Man-Of-War and somehow (I would not advise this) scooped it into a bucket. Then another family brought theirs over and they arrived home to a very shocked me with a bucket full of Portuguese Man-Of-War!


They are beautiful creatures, although we know them to be harmful and occasionally deadly. In reality they are also very stunning. Their balloon like float was a blue/purple tinged bubble with incredible spiral "springy" tentacles which boinged up and down like a coiled spring. I was completely mesmerised. You see photos of creatures such as these but in reality they are just so incredible and awe inspiring!


So what are they? Jellyfish they are not - they are in fact a great example of team work. They are a "siphonophore" and are made up of 4 individual animals with 4 individual functions that are merged to create one animal. They use their stings to prey on small fish and shrimps and catch them through paralysis. They don't, as some might imagine, have stings to purposefully set out to find naked skin and sting - it is just a highly advanced adaptation to catching prey in a mobile and aquatic environment. They use their gas filled chamber quite literally as a sail to blow their way across our oceans in great swarms. Normally, they are found in tropical and sub-tropical waters but occasionally individuals get blown off course and end up in foreign waters such as the 2 found in Bantham today.


The venom is harmful and tentacles and the animal should be avoided. If you do get contact seek immediate medical advice. At this stage there is no need to worry about them in our waters...but be aware, be careful and inform a lifeguard if you see one.

Monday 27 July 2009

Magnificent!

What a lovely day! After a particularly wet & challenging day yesterday (despite previous post's optimism) I was greeted by blue skies this morning! I had a booking with a group that had been out the previous week and had made a repeat booking today. They were a pleasure last time and we'd had a great time rockpooling and making seaweed presses. So for an alternative I got my laptop and digital microscope out for some magnifying fun!

It worked a treat and we had a look at the underside of a cushion starfish and all the amazing suckers that run down the length of the 5 arms. The little suckers were stretching out in every direction to find a surface to adhere to and just looked incredible under magnification. The children loved it and were equally stunned when we did a mini experiment in the back of the "Van Lab".

If you take some coral weed, I had been told, and put it in some vinegar the calcareous skeleton on the outside of the coral weed would dissolve. Luckily, I had some vinegar in the van for cleaning the windows - much better than nasty chemicals - and so I put a small piece of coral weed in a small microscope tray and added the vinegar...Hey Presto!! As quick as you can say "Starfish" the weed started bubbling away which we could see so well with our laptop/microscope set up. As the calcium carbonate dissolved in the vinegar bubbles of carbon dioxide appeared and the stony skeleton simply dissolved away to leave some naked, filamentous seaweed. I'm not sure who was more excited the children or me! Either way it was great to see some real science under the microscope and have children so engrossed. Science is so much fun when it's hands on and children can directly experience science before their very eyes! It makes it all so worthwhile to see children having so much fun and learning at the same time.

So there will definitely be more "experiments" in the Van-Lab after today's magnificent day!

Tuesday 21 July 2009

Rockpools "made a dreary day fun!"

So today was pretty wet as far as Summer days go (compared to 2007 anyhow!!). I have to admit I woke up to the sound of rain and and just felt a bit let down! Rockpool ramble trips are under full swing at South Milton Sands now the holiday season has started and Learn To Sea is fully booked every day until next Monday come rain or shine!!

Well, I donned my (usually Winter) waterproofs and marched off to South Milton to face the music! I was greeted by a lovely family who were due to come out with me on a guided rockpool tour. Luckily, they came prepared and with a great British constitution of sheer stubborn mindedness in the face of rubbish weather. So, off we trotted...There are drawbacks to wet days rockpooling. Where we would normally head to the stone arch - it proves too difficult and slippery on a wet / windy day. So we ventured to a different more flat area of rocks.

Luckily, I knew from previous experience that while we wouldn't find some of the more unusual finds at the stone arch we would see some real gems. But it was one of the best rockpooling trips in a long while! Lots of starfish, netted whelks and many other creatures to show the families. They were beautiful rockpools that ran the length of the bedrock to the sea which were teaming with colour and life. We were so engulfed in our explorations that we completely forgot about the rain! The fact that the day was so wet made it seem even more exhilarating to be out exploring regardless of weather conditions.

I'm so glad that all the visitors are such hardy creatures and have good waterproofs! While we may hesitate at the thought of going out on a wet day - the rockpool creatures are still there to be found. We still managed to make some lovely seaweed presses and avoided any terrible daytime television or thumb twiddling.

The feedback form for the day said "Maya made a dreary day fun!" I would agree we had fun but I just facilitated it - it was the rockpools and good company which made it so much fun. I, for one, am looking forward to some more rainy days out rockpooling... although I wouldn't complain if it was sunny too!!

Wednesday 8 July 2009

BBC Springwatch

http://www.bbc.co.uk/blogs/springwatch/2009/05/at_the_beach.html

For those that may have missed it - here's a clip of the Springwatch piece shown in May and June this year...it was so much fun to do. I really enjoyed working with the Beeb and they were so friendly and fun to spend the day with! It's also great to see that there is so much interest in the media world of all creatures small and marine. It seems as if people are really getting back into British wildlife. There's so much to see and do on our shore and such a wonderful variety of coast to visit. Naturally, none better than South Milton Sands of course!

I've got antique Sea-shore guides and seaweed press books going back to 1880 and it's great to see people get back into doing things our forefathers and mothers(!) did before us - like the wonderful seaweed presses. One obvious improvement in the way we act on the shore is our adoption of the "Seashore Code". In the "old days" they would say to "collect more rare specimens for your aquarium tanks"(!) - now we say "Leave only footprints, take only photos." It appears that perhaps we have learnt some valued lessons about conserving our intertidal creatures but not lost some age old brilliant games and activities! for more information about the "Seashore Code" check out the website - http://www.learntosea.co.uk/

Barnacle Bill!

Our intertidal zone, where the land meets the sea, is an area that has always intrigued and fascinated me. The thing that never ceases to amaze me is that the more you know about life in the rockpools the more intriguing and incredible it is. Even the most ordinary looking creature is extraordinary through its habits, feeding mechanisms and reproduction. They live in such a harsh environment – what we experience seasonally in a year – they endure in 12 hours. In one tidal cycle they have to survive extreme conditions. They go from being below the waves in a fairly constant cool temperature and salinity to having the tide dropping and, on a Summers day, the water in the pools heating up rapidly. The salinity increases as water evaporates and the amount of oxygen in the water drops as does the amount of food around them. Conversely, they have an increased pressure of predation in this now smaller environment. The tide rises and they have the fear of the waves smashing their bodies against the rocks. It is this unique and stressful environment which leads to some of the incredible habits and body shapes and structures of our intertidal creatures.

I love dolphins as much as the next person and if anybody asks what their favourite marine creature is many will say – dolphins, whales and seals. These are our iconic sea mammals and we feel a sort of spiritual connection with these intelligent and expressive animals. It’s a shame that there is not more coverage of some of the smaller creatures that may not have the expressive eyes and acrobatic skills but are none the less amazing animals. Let’s take a look at the barnacle for example. Barnacles are really quite incredible creatures that many people may curse when they walk over the rocks because of their sharp volcanic homes that they create.

Barnacles have an incredible life cycle - relatives of the crabs, lobsters and prawns they are classified as “Cirripedia” and Darwin did much to clarify the classification, different body shapes and various life cycles of the lowly and numerous barnacle species. He was the one to point out that they were not molluscs like mussels, periwinkles and other bivalves but actually crustaceans.

They start off life as much of our marine intertidal animals do as a larval stage – but not just as one but two stages. It starts off as a “naupilus” a free swimming, one eyed planktonic creature. After several moults (just like a crab moults) it develops into the next more complex stage which is called a “cyprid” and here they search out a place to call home. They use structures called antennules, like antenna, to find a good spot to settle for the rest of its sedentary life. Once it’s found the perfect spot it cements itself to the rock with its head...very strange behaviour. Once attached the cyprid then creates a sturdy, rocky, volcanic looking home around its delicate body – this takes about 12 hours. Now, it looks like the barnacle that we all know.

Once settled, it starts its cyclical feeding on the high tide. Cirripedes means “curl footed” in Latin and it is this apparatus that it uses to scoop out tiny bits of food from the water. On the low tide to protect itself from predators it closes a trapdoor and rests in its own cool pool of water as the tide drops. But if it’s stationary how does it reproduce with its neighbour? Well, this is another fascinating area of the barnacle life cycle – with a long (largest relative to body size in the animal kingdom) extendable phallus the barnacle searches for a neighbouring female and fertilizes her externally. Once this has taken place the phallus then falls off! Once the fertilized eggs are “hatched” into the naupilus larvae they are released into the water column and so the life cycle begins again...amazing stuff! You might have thought the different life stages of a frog were amazing but what about that for a life cycle! So, this Summer next time you look at a barnacle take a minute to think about the extraordinary lengths it has gone to to get where it is!

So, there we have it - a seemingly insignificant creature that has got to be respected for its incredible life cycle and fight against the odds for survival in this harsh and intertidal zone.

And in the beginning there was...

Welcome to Learn To Sea's new blog site - here I will post any new info about what has been seen rockpooling lately...what Learn To Sea is up to and any thoughts for the day on marine issues.

Hope you enjoy!