Marine Iguanas - A Lizard On Its Own

So this post follows on from the article which was posted on Wednesday, which concerned the idea that islands cause the evolution of weird and wonderful animals, due to their isolation and other contributing factors.

The animal which we will be looking at in this post is the Marine Iguana or Amblyrhynchus cristatus, which can only be found on the Galapagos Islands. This species is unique among modern lizards and one of only a handful of reptiles which take to the sea to feed. Clearly being a reptile is problematic for a marine existence as the cold sea water will slowly leaches an iguanas heat from its body and being ectothermic an Iguana is unable to replace this lost heat. The iguanas are able to overcome this however by spending a lot of time bathing in the sun and thanks to their colouration they are capable of quickly absorbing heat. Along with this iguanas are usually found along rocky areas of the coastline, this allows them to gain maximum exposure to the sun whilst out of the water, along with being able to absorb heat radiating from the rocks they sit on.

However when an iguanas body temperature does drop it will like all reptiles become slower and react sluggishly to stimuli such as the presence of a predator. Therefore iguanas have evolved a behaviour to deal with this issue, when threatened a cold individual will display high levels of aggression in an attempt to postpone potential attacks and create an escape route. However even with these behavioural responses Marine Iguanas are still in decline as introduced species such as cats, rats and dogs have been seen to prey upon them and so as of 2004 Marine Iguanas are rated as vulnerable on the IUCN red list. Also due to the fact a survey on population size has not been carried out for 12 years and the known negative effect of climatic phenomenom such as El Nino have on marine Iguanas means that potentially there are currently fewer Marine Iguanas than is believed.

Events such as El Nino have a negative effect on population numbers (up to 85% mortality rates) due to a number of reasons. For instance the event in 1982-83 caused high rainfall which flooded nests, increased sea levels which meant that a higher proportion of their food source was found at a depth iguanas could not achieve and finally increased surface temperatures which reduced the marine productivity of the area and so reduced food sources yet further.

Marine Iguanas feed primarily on 4-5 different red algae species along with a less favourable but more common green algae species with the regional feeding zones being dictated by the size of an individual. Smaller individuals tend to feed in the intertidal ranges where food is easily available and diving is not needed, while larger individuals feed further out. Dives are typically to depth of 1.5-5m but large adults have been seen to go to depths of up to 3 times this.

Throughout their time spent feeding Iguanas are constantly absorb excess salt from the water. To deal with this issue these iguanas have evolved special nasal glands which allow them to excrete the excess salt from there system with a method which looks like they are sneezing. This is extremely beneficial for iguanas as if the excess salt had to be passed out through their urine they would require vast quantise of water to allow them to perform such a process.

So overall Marine Iguanas are a perfect example of how island ecology gives rise to creates you would never see in mainland populations.

There is a tonne of other resources out there on the web for anyone who wants to find out some more on these amazing animals, but I’ve linked two good sites just to get you started.

http://www.arkive.org/galapagos-marine-iguana/amblyrhynchus-cristatus/

http://www.iucnredlist.org/details/1086/0

Thanks for reading!

Check out these videos!

Weekly Article - Islands Are Weird Places

So I've finally finished my degree so at least for a while hopefully I'll be able to consistently post.

Jumping straight in again, check out this article.

http://sciencenordic.com/islands-make-large-animals-shrink-and-small-animals-grow

This article touches on the weird and wonderful world of island genetics, with a small gene pool and commonly limited levels of  immigration and emigration makes many islands a weird and wonderful place.

Commonly the more isolated the island the generally 'weirder' the ecology of the region. Example of this can be seen across the world with a key example for instance being New Zealand where we can find animals such as the Kakapo or the dwarf elephants from the island of Crete which were mentioned in the article.

Thanks for reading!

Stay tuned for the next post

Fur - A Product In Demand

Hopefully this blog will begin to have consistent postings within the next few months as unfortunately I simply don't have the time to post at the minute.

 However saying this I have something I think a lot of people should see. This BBC documentary is looking into the issues of the fur industry in the consumer cultures we live in. Wearing fur was considered controversial in the past but it appears that the stigma of wearing fur is being lost as markets change.

If you can get access to this take a look. (WARNING: contains some upsetting images)

http://www.bbc.co.uk/iplayer/episode/b07955p4/this-world-inside-the-billionaires-wardrobe

Thanks for reading!

Growing Your Own Food - How Hard Can It Be?

I’m sadly going to have to keep this post brief as well as I have a deadline this week which is taking up all of my time.

So it has been spring for about two weeks now and the weather is starting to warm up, in the UK at least. The growing season is starting and you don’t have to have a huge garden to be able to grow some of your own food.

I have already touched on the environmental costs it takes to be able to put food on the table, with transport and land clearance etc. I thought it might be a good time to remind everyone that you can always grow your own. The average family only needs half an acre of fertile land to be self-sufficient if they do it properly. However that also requires a lot of time and effort which the majority of people don’t have freely available, so there are a few ideas of plants which are tough, easy to grow and taste great.

Potatoes would be one of the first plants I suggest you grow, I mean if Matt Damon can grow them on Mars how hard can it be?  But seriously potatoes are a good crop to start with, which you can do so much with and a great healthy source of nutrition. To plant potatoes all you need is some space or a large bag of soil, try to remove most of the larger stones and place a potato which has developed eyes on it about 15cm below the surface. You should try to water them as regularly as possible and the muddier the better when it comes to potatoes, but you can easily get away with watering them twice a week if you can’t find the time. The final good thing about potatoes is that if you grow a large amount you only need to keep them in a cool dark place and this will keep them fresh for a long time.

Another easy type of plant to grow would be either runner beans or broad beans; these can even be grown in compost bags. All you

have to do is lay the bag on its side then cut a few holes in it and place some form of structure there which the plant stem can grow up. Again these are hardy plants that don’t necessarily need watering every day and a couple of times a week would be suitable.

The final easy plant to grow I would suggest is lettuce, they can be grown in small plant pots even on a kitchen window sill if you don’t have the space outside. They are great to have around as you can just picking a few leaves of at a time to put in your sandwiches or a salad.

Growing your own veg is a fun and an activity you can sharing with your children for instance, and you gain a real sense of achievement when you sit down to a meal eating something you’ve grown in your own back garden or window ledge, and anything you grow will not have create any pollutants to get to your table.

Hope you have a good time growing.

Thanks for reading!

Check out this video!

Weekly Article - Communication Is Key

After just having a couple of lectures which focused on the behaviour and ability of animals to communicate with each other, I found these two interesting articles. They highlight how humans are not the only species to have advanced communication skills, although of course they are the most advanced species in terms of communication.

These types of studies are extremely important because not only do they allow an insight into the evolution of language and suggest how human communication began and evolved, they also give an insight into the behaviour of the subject species and so provide more information about reaction to stimuli and how the species react and interact as a group.

Communication makes up the bedrock of society and whether its simply warning that a predator is near or long complex sentences, without it no social structures we see today would exist.

Check out these links!

Japanese bird species using syntax
http://www.redorbit.com/news/science/1113413008/non-human-syntax-030816/

Wolves have howling dialects
http://www.cam.ac.uk/research/news/wolf-species-have-howling-dialects

Thanks for reading!

Madagascar Pochard - Back From The Dead, But For How Long?

So the animal I want to talk about for this post is extremely rare and not very well known, leave a comment below if you’ve ever heard and how that was. I had never heard of it, till a few months ago through a piece of work I had to do. Yesterday I was lucky enough

to learn about some of the work which is going on at the minute to save the world’s rarest bird from extinction.

The species I’m going to be talking about is the Madagascar Pochard is a bird which is endemic to Madagascar and until 2006 was believed to have become extinct around 1992. However 22 individuals were discovered in a single lake in the north of the country, since then the Durrell Wildlife Conservation Trust and Wildfowl & Wetlands Trust in Slimbridge have undertaken the responsibility to help save this species whose future is in a very precarious position. They have had several successful breeding seasons over the past few years and the species is now made up of around 80 individuals in both the captive and wild populations.

Starting with a bit of background on the Pochard, it is believed that the species began to experience dramatic declines around the 1940s-1950s; these declines were initiated due to the introduction of invasive fish preying on chicks as well as hunting, gill nets and the destructive effect of grazing animals coming down to the water’s edge and so destroying their nests. They are a medium sized duck 45-56cm with the males possessing rich brown mahogany feathers with white underparts. As a diving duck it primarily feeds invertebrates with slight supplementation from plant matter. As for breeding behaviour, nesting has been observed from July to February with nest sites usually being sited within close proximity

of waterbodies in vegetation.

A vast amount of effort is currently being put into the Madagascar Pochard, the aim is to first bring their numbers up to a viable population so as steps can be undertaken to reintroduce animals to new locations to allow the species to become more structurally secure.  As well as this an attempt is being made to place legal protection on areas which have had little disruption from human activities such as Lake Alaotra. The final step being taken is a continued extensive search in the hope of discovering more isolated pockets of the species. It is important that if any other population which currently remain in the wild are found as currently one of the major problems the Pochard has is the genetic bottleneck which it has been forced through so any individual found will help increase the size of the source gene pool.

A genetic bottleneck occurs when a species experience reductions in their population size and in turn this reduces the size of the potential gene pool for the species and so can increase the representation of certain recessive genes which have a negative influence on the species fitness and survival rates. Genetic

bottleneck have been seen in multiple species, such as the Mauritius kestrel whose numbers fell as low as a single breeding pair in 1974 to 200 breeding pairs in 1990. So a bottleneck does not mark the end of a species by a long way, it does however require extensive stud books to be kept in captive population in an attempt to limit the genetic loss from the species gene pool.

So if you want to help this cause along with their other projects the Wildlife & Wetland Trust and Durrell Wildlife Conservation Trust are working on such as the Madagascar Pochard and the Spoon-Billed Sandpiper you can of course donate online. But if you want a good day out as well, head to one of their reserves to lend your support and see some amazing wild fowl. Currently a lot of the breeding seasons are about to start and so there is lot to be seen and enjoyed.

Thanks for reading!                                                            

Check of this video!

Weekly Article - Zombie Frogs Are Among Us

Sorry for it being a bit late but I'm completely snowed under with work at the minute. This weeks article is right in my ball park in the fact that is concerning amphibians and chytrid fungus.

I don't want to say to much as I've already written about the decline of amphibians on this blog.

So I'll just let the article speak for its self, apart from the fact that its methods like this that show just how amazing the natural world is and makes you realize just how little we know about it.

Check it out

http://www.sciencemag.org/news/2016/03/fungus-turns-frogs-sexy-zombies

The decline in amphibians post

http://littlechangestoday.blogspot.co.uk/2015/10/decline-of-amphibians-bell-frog.html

Thanks for reading!