Arquivos de periódicos de fevereiro 2019

02 de fevereiro de 2019

Stange Growth Seen in Forrests

A mysterious green unicellular desmid seen in cloud forests throughout New Zealand tag name "Gollum" - as in something the infamous, literary character Gollum would cough up.

A couple of obs of this strange organisim
Info as to where it can be found
Another obs

Posted on 02 de fevereiro de 2019, 11:17 PM by tangatawhenua tangatawhenua | 0 comentários | Deixar um comentário

08 de fevereiro de 2019

Distinguishing Glaucus atlanticus and Glaucilla bennettae

There are two species of Glaucus / Glaucilla that wash up on our shores and in some ways they are the stars of the blue fleet as they are not seen as much as the other members.

These float upside down, so what is visable when looking down into the water is actually the underside, while what is seen from being in the water looking up - usually just white / blue without the colour variations - is actually the dorsal, or top.

The sea swallow - Glaucus atlanticus can be identified by the two dark stripes with a silver strip inside them visable when they are floating in to water - this is the foot. G.atlanticus is larger, up to about 30mm, and also has a longer tail.

Glaucilla bennettae (old name Glaucus bennettae) has two dark stripes that are have a blue strip inside them, instead of silver . G.bennettae is smaller - about 12-15mm and the tail blends in with the "frilly bits". This species tends to have a "glitter look".

If you ever come across a washup take a close look at different Glaucus, as once you spot the difference they are easy to tell apart, even at a quick glance. Below is a photo with both of them so you can see easily the differences. What is showing is the underside of the creature, but this is what is seen from the top of the water.

Right: Glaucus atlanticus Left: Glaucilla bennettae

Most of Blue Fleet Welcomes Me Home is a journal post I have done about these.

Posted on 08 de fevereiro de 2019, 02:50 AM by tangatawhenua tangatawhenua | 4 comentários | Deixar um comentário

Most of Blue Fleet Welcomes Me Home

Usually when I return home after being away, the first chance I get I'm in the water and usually welcomed by wheke which we all know are common and easily spotted :D

However, the first time I went down to the beach the water was rough, with white caps everywhere and I did not fancy photographing sand particles in good focus with a creature lurking in the background of the photo, so we did a hikoi (walk) along the beach instead.

The tide was on its way out and up in the high tide mark I spotted Janthina - photographing those in strong winds is a mission as those shells are light! LOL Then heading towards the water, in the next wash line, were by-the wind sailors and then I saw the blue buttons.

Aha! He tohu tena pea? A sign perhaps? Surely if there were a few blue buttons around then those elusive Sea swallows, Glaucus atlanticus, will be around somewhere. So heading towards the water again, sure enough on the next wash line there they were! Totally stoked to see these again.

Of course, when I first found the Blue Fleet I did not know at that time that there were 2 different species that wash up from the Glaucus whanau, and as this was the first time I had seen them since then, this was the ideal opportunity to take a very good look at them and see if I could spot the two species clearly and sure enough. After lurking and studying and looking closely, the two species are easy to spot, as seen in the photo below :)

Right: Glaucus atlanticus Left: Glaucilla bennettae

I also noticed that the Glaucilla bennettae were all together further down the beach while where the Glaucus atlanticus were, there were also a few of the Glaucilla bennettae. So maybe the Glaucilla bennettae prefer to hang out by themselves.

However, the blue bottle - the most common of the blue fleet was no where to be seen!

Further Reading: Distinguishing Glaucus atlanticus and Glaucilla bennettae is a post I put on the Blue Fleet Monitoring Project.

Posted on 08 de fevereiro de 2019, 09:14 PM by tangatawhenua tangatawhenua | 7 observações | 6 comentários | Deixar um comentário

15 de fevereiro de 2019

Poor Knights Island Marine Reserve

My curiousity abut the Poor Knights was triggered when I took @pjd1 down to the G2 a couple of years ago. After putting his head underwater, he popped straight back up and said, "This is amazing! I have not seen this much diversity on mainland New Zealand!"

"Huh?", says me, "this is normal."

"No, this is not normal on the mainland. I have only seen this richness of diversity at the Poor Knights and the Mokohinau."

Since then I have been to a few beaches outside of my rohe, and I started to understand what he meant and came to appreciate home more and more as I saw places that have been stripped of marine life and you have to hunt to find things instead of choosing one area and spending hours lurking there and still not have seen everything there is to see. Now when I visit a beach that is not at home, before I go I say to myself, "This is not home, it will not have the diversity," which helps because I enjoy the places that I have been to.

This year my son and I finally made it to the Poor Knights so I could to see for myself what it is like out there. Naturally the weather was great, the skies blue and only about a 1.5m swell. A Buller's Shearwater escorted us over to the Poor Knights, easily keeping up.

The water was clear with good visibility down at least 10m in most areas so it was easy to see fish and brown alga. Along the rock face (where the island plunges into the sea) the demarkation line between the different tides zones was very noticable - almost like someone had drawn a line and from there down different red alga grew and were not seen above the line. With the swell it was really helpful to be risen up to see that zone, then taken down to see a zone below.

Upon departing we went for a look around some of the other islands. The photo below was taken then, showing two "Hole in the Rocks"

Overall we had a great day, exploring a new place. Alot of other people on this trip were blown away with the thick weeds and lots of fish. For anyone else this would be a spectacularly mind blowing place!

We however can see all of this in our own backyard, the thickness of the browns and at times lots of fish swimming around, coming up close like they did here. We are also interested in all marine life so spent a good hour and a half following along the rock wall for about 100m to see what we could find and the answer was not much. When I do the same thing here I am lucky to do 20m in that time because of the many things I see and stop to photograph. However, that could reflect that this was a completely different ocean enviornment and that is why the diversity in the area we explored was not as great as the diversity at home.

This trip was not disappointing as finally seeing it was worth it, but has strongly re-enforced how amazing home is and has given both of us an even greater appreciation of our own backyard, where we do not have to take a 25km boat ride out to sea, instead, just a short drive then walk and the wonderland is there for the exploring :)

Posted on 15 de fevereiro de 2019, 06:06 AM by tangatawhenua tangatawhenua | 8 observações | 0 comentários | Deixar um comentário

22 de fevereiro de 2019

Baffling Bluebottles

Physalia physalis which we have been using to ID the blueblottles found here does not exist here. Those are an animal that grows to 30 cm, a near full crest, and a large number of tentacles that can extend to 50 m and I am sure we will all agree that we have not seen anything that large in all of our bluebottle obs.

So what do we call ours? Well there seems to be four possible ID's for our ones.

Physalia utriculus (top left) has a single main fishing tentacle, a float with a high crest in the middle half of the float and long, cylindrical, tapering, posterior extension (right hand side). They can also have a bloated float.

Crested Bluebottle - Physalia sp1 (full crest) (top right) has one single main fishing tentacle, and a prominent crest along the full length of the float which does not stand up high like the Physalia utriculus crest, instead it shows more as "joins" as seen in the sample photo.

Barrel Bluebottle Physalia sp2 (no crest) (bottom left) has a single main fishing tentacle and no crest. The float is also smooth without any "joins" but you must turn the float to make sure that the "join" was not sand down.

Irukanji Bluebottle - Physalia sp3 (multi-tentacled) (bottom right) which has multiple main fishing tentacles. These are the long ones and we can see in the photo that there are at least 2 long ones.

The crest is the main thing to look at as what it is will eliminate most of the other species. Next would be the number of main fishing lines although it is really obvious when there is more than one.

Further Reading
This Obs with lots of korero
Flag for Physalia Genus
Photographing Bluebottles
Bluebottle Guide - Coming Soon

Posted on 22 de fevereiro de 2019, 04:51 AM by tangatawhenua tangatawhenua | 0 comentários | Deixar um comentário