Does the evidence from a new study suggest that Burmese pythons are responsible for native species deaths in Florida's Everglades

Building upon the topic of my last post, it has now been suggested via a year long study that Burmese pythons (Python molurus bivittatus) are responsible for the death of native species within the Florida Everglades.

What they did
A team led by Robert Francis of the University of Florida captured native marsh rabbits (Sylvilagus palustris), fitting a total of 95 trackers to adults that included a mortality sensor which notified them of the animals death. The rabbits were then released onto three separate sites, two sites had pythons present whilst the third had no observed pythons present. The team stated that they chose marsh rabbits for the study due to their prolific breeding habits suggesting, that it would be harder to wipe such a species out.
The rabbits were radio tracked at least once every two days and any carcasses found were examined for cause of death; predation by either the python or alligators was easy to detect as it was often still located within the body of the animal. Two carcasses which were found were also tested for traces of python DNA.

What they found
Once the year long study had been completed, the findings showed that only two rabbits had survived, with the team documenting a total of 68 rabbit deaths (If like me you are wondering what happened to the other 25 rabbits which were tracked to make up the total of 95, it does not mention them so unfortunately I can not provide an accurate answer other then to guess that they were not retrieved). In the areas of the park where pythons were present it showed that they were responsible for 75% of the deaths compared to 71% in areas where they were not present which, were were caused by mammalian predators, leading them to suggest that the pythons were the main threat for the species decline.

 

My Views

Firstly I am drawn to the conclusion made by this study, how can it suggest that the python is any more of a threat to the species when the two percentages are so similar? Surely all this data would suggest is that where pythons are present they are the new apex predator and therefore are out competing other native mammals for the same food source meaning, that the python is more of a threat to the native predators which it out-competes, then to the marsh rabbit which it preys upon as, the rabbit is still preyed heavily upon by mammalian species where the python is not present.

Secondly this study is again being used as a reason to back Americas reasoning that exotic species such as the Burmese python should be banned from ownership but again alike a lot of the studies that supposedly support this theory there is often plenty of misinterpretations that are too questionable to allow these studies to be used as evidence. I agree that the pythons are a invasive species and should be removed from the area but I do not agree that it should result in a ban of a species as a result; over the years thousands of domestic species such as livestock i.e. pigs and goats and dogs and cats have escaped and become feral across America and the rest of the world and not once have I heard of any of these countries banning the ownership, or importation of any of these species; it seems that because there is so much stipulation and poor education about exotic species such as reptiles and snakes that they become an easy target for eradication but they are many reptile owners out there who love and care for there bearded dragon, corn snake or Burmese python as much as any cat or dog, rabbit or guinea pig owner loves their pet, they are part of their family just as much and I only hope that with a bit of education and understanding it will be that way for many more years to come.

 

As always thanks for taking the time to visit and read my blog and if you would like to share your opinions then feel free to add them in the comments box below :)

To view the original paper click here 

A dark day for the reptile community. Four new snake species added to the Lacey Act

Reticulated Python, one of the new species added to the Lacey Act.

On the 6th of March the United States Fish and Wildlife service announced that four species of large snake are to be added to the Lacey Act; these are the reticulated python (Python reticulatus) and three species of anaconda, the DeSchauensee’s anaconda (Eunectes deschauenseei), green anaconda (E. murinus) and beni anaconda (Eunectes beniensis) which join the Burmese python (Python bivittatus) which is already on the act.

So what is the Lacey Act?
The Lacey Act was passed in 1900 to aid in protecting wildlife by inflicting strict penalties on anyone trading animals and plants illegally and regulates the import of any species protected by international or domestic law and thus prevents the spread of non-native/invasive species. For more information about the act please click here for the US fish and wildlife service official explanation of the act.

So why are these snake species being added?
The Burmese python was originally added to the Lacey Act as a result of the spread of a invasive population that had been released by suspected pet owners, who could no longer manage them, in the Florida everglades. These snakes have had a supposed detrimental effect on the local wildlife populations, by preying on species such as birds and some endangered species. It is interesting to note however that local residents from the everglades state that most have never seen a Burmese in the everglades and that other invasive species such as stray cats and pigs are more prevalent and have more of a negative effect.
The four latest additions are not actually found as an invasive species anywhere within the United States and have been put on the act as a precautionary measure suggesting, that they might become an invasive species in the future; a interesting view on this was provided by Brian Barczyk from BHB reptiles and who runs the popular online show animal bytes, he stated 'it is like putting someone in jail because they might commit a crime.'. None of these snakes could survive in the wild in northern states due to the cold climate and therefore could never become an invasive species, this poses the question of why should the entire population of reptile owners be punished for a incident that has only occurred in southern Florida? and why are other more invasive species such as stray cats and pigs not included on the list for the same reasons?

The green anaconda another addition to the act.

So how does this effect me?
If you live in the United States and own one of these five species, you can still keep them and if you wish breed them but you can not cross state lines with them or you would be breaking the law which, carries a sentence of up to five years in prison if they press charges. This means that if you had to move between states then your snake can not come with you, leaving you with the option of staying put, trying to re-home the snake or the one that no pet owner should ever have to face, euthanizing a healthy animal because of a misjudged law.

I do not live in America, how does this affect me?
Unfortunately it is only too common that once one country adopts a policy like this, that others start to follow and already within the UK, the announcement that the Scottish government wants to review its exotic pet trade act, could result in not just the prevention of keeping snakes but also other reptiles, fish, small mammals and birds.

So what can I do to help prevent/fight against this?
In the US the USArk has filed a federal lawsuit against the US fish and wildlife service for their use of poor reasoning for why this law has been passed. To find out more about USArk and to find out how you can help in the fight against the Lacey Act please click here  to view their site.
For UK residents a petition has been started by the Federation of British Herpetologists against the Scottish government, to sign the petition please click here and to find out more about it please click here to visit their website.

Finally I shall leave you with a video by Brian Barczyk owner of BHB reptiles, the animal bytes online video show and who is passionate about educating people about reptiles, having helped myself and friends with our own snake questions as well as providing breeding advice. This video discusses the Lacey Act and the effects it will have on the reptile community which brought tears to my eyes.

   

Reciprocating rats! Rats more willing to help those that help them.

Humans are familiar with the concept of returning a favor if someone has helped them, this is known as reciprocity and is a favorite explanation for how co-operative behaviors evolved. In nature this behavior is difficult to study, this could be due to it being rarer then thought in nature or because it is a behavior that is difficult to measure in the field.
A study by Dolivo and Taborksy looking at Norwegian lab rats (Rattus norvegicus) found that the rats give as good as they get. Following the principle that this behavior is hard to study in the wild and therefore using a controlled laboratory environment instead; they trained the rats to pull a stick that issued food items to a rat in a adjourning cage which could see the the rat dispensing the treat through the cage. They then expanded on this by placing a rat in between two cages containing rats on either side. The cage on the left had a stick that upon being pulled dispensed a carrot treat to the central rat whilst, the cage on the right had a stick that dispensed a banana treat to the central rat. The central rats generally favored the banana treat therefore, this would suggest that the central rat would favor the right side rat that dispensed the banana treat and would be more willing to help banana providing rats than carrot providing ones; this turned out to be true with rats that provided better help (banana) receiving greater rewards as a result, indicating reciprocal behavior.

 
These results therefore clearly show that rats have the ability to recall not only which rat helped them but the quality of help received as well, adjusting their behavior accordingly as a response. Adding this onto previously studies undertaken by Taborksy's team that rats are more likely to help a partner that has aided them before compared to one that had not; it provides a interesting insight into how a species manages the challenges of co-operation.
However it is not just rats that have displayed the ability to reciprocate, a study by Melis et al (2006) demonstrated how chimps theorized which partners to choose, based on previous experiences, when embarking on tasks. It has also been seen with fish that use cleaner fish, these client fish as they are often referred as, will often favor cleaner fish that behave in a more co-operative manner. Lastly even pied flycatchers have been observed favoring other flycatchers that actively aid them in mobbing owls in their territories.

All these examples clearly show that reciprocation is used within the natural world as, it provides a benefit to both animals involved and that those who help more will receive more in return; this behavior possibly aids in forming stronger bonds amongst social groups allowing those who aid the group to be favored over those that do not.
To view the original article Click here. 
Thanks for reading and as always feel free to leave any additional views or comments in the box below :)