This view needs a little explanation in order to inspire awe. This is a photo taken on Fraser Island, the largest sand dune island in the world. It is about 123 Km in length and 22 Km wide (76 miles long, 13 miles wide), and still growing. The sand comes from the erosion of the near by mountains in the Great Dividing Range, and gets blown out to sea and dropped on the island. This results in huge sand dunes which slowly move through the island and build it up and out. This is a picture of one of those sand dunes. You can see dead trees poking through the middle of the sand, and those are the tallest ones. The rest are buried under a lot of sand.
Saturday, September 27, 2008
Thursday, September 25, 2008
This is the Tasmanian Devil or Sarcophilu harrisii. They are found on the island of Tasmania, however they used to roam all of Australia. They were hunted on Tasmania up until they became protected in the 1940's. They were seen as a threat to the livestock, despite the fact that they are mainly carrion eaters, and rarely hunt. They are the largest carnivorous marsupial since the extinction of the "Tasmanian wolf" or Thylacine in the late 1930's.
The current populations of Tasmanian devils has been upgraded from vulnerable to endangered just this year. The decline in devil numbers has been drastic, with a estimated drop in numbers from 150,000 to 50,000-20,000 individuals in just ten years. The cause is a particularly virulent cancer which causes facial tumors on the devils. Once contracted, they die within a year to a year and a half.
The cancer can be spread from one devil to the next by contact (mainly bites). As matings frequently involve biting, and feeding is highly social (devils will call others to a meal) the disease has spread very easily and rapidly. Researchers have been working hard to figure out this issue, and they have found that because the devil's numbers were so reduced, that their immune system is not very genetically diverse (esp. MHC genes). Because of this cancerous cells from an infected individual are not rejected by a healthy individual because they are not considered foreign cells by the healthy individual's immune system [1, 2].
In an interesting response to this decreased life expectancy, the devil population is undergoing a shift in sexual maturity. Devils used to reach sexual maturity at two years of age. Now a high proportion of the population is sexually maturing at one year of age. This shift gives them a better chance to mate and produce offspring before they die .
Sunday, September 21, 2008
I did not find anything really weird this year. I think the strangest thing I found was a flip-flop, but I did manage to collect over 2 pounds of trash in an hour and a half. In the back you can see what other people collected. It was kind of sad, because the largest pieces of trash I collected (aside from the flip-flop) all washed into shore while I was standing at the water's edge. Trying to collect all the trash that was washing up while we were doing the cleanup was a little like holding back the tide. But it was great to see all the people who participated, and see the truck of trash that was taken away from the beach.
Then it was off to pick up my husband to go to the annual marine biology association party. I got there before he got off work, so I gathered my courage to check out the spider pavilion near by.
I was expecting to see normal-sized spiders chilling in the trees. What was there was three inch long (excluding the legs!) monsters... There were five types of spiders present, I only found three. The above is a golden silk spider.
There were giant webs strung everywhere, even above the walkway, which made me really nervous. Especially with those giant spiders sitting in the middle of them. The webs didn't look like the would be able to support the weight of the spider (although I know they could). I was expecting one to drop on my head at any moment. It was cool, but I don't think I've conquered my fears with that visit.
Then it was on the the party itself. It was held at my favorite aquarium, so in between chatting with people and eating nibblies, I got to see what was new at the nursery.
What was new was two day old octopuses and day old squids. They were so cute! The octos were about an inch in diameter (including the tentacles), and the squids were 1/4 to 1/2 of an inch long.To top it off, I won a nice octopus picture from the raffle. What a great day!
Saturday, September 20, 2008
I took this picture of the Sonoran Desert on the road heading back from a meeting in Arizona. At the time, my boss bemusedly wondered if I could get any good shots while the car was moving... I'll leave that up to you to decide.
Those tall green spikes seen in clusters around the right base of the hill are Saguaro cacti. Apparently, they only grow wild in the Sonoran Desert, and take a long time to grow. Estimates have these cacti living for 150-200 years, and a 10 year old cactus is only 1.5 inches tall! If you want to learn more about the Sonoran Desert and the research that is taking place there, see this really neat website.
Thursday, September 18, 2008
Wednesday, September 17, 2008
She is still laying eggs however, so I remain somewhat hopeful. I've got a second small tank set up with a 1: 3 mixture of oats and sand and am transferring half of her eggs into that tank. Other mealworms (often used for feeding) are raised on oats, so I am hoping that a high concentration of possible food will help the process.
Iron clad Egg
I still believe that temperature has something to do with it. Today I put her tank in the sun, and the thermometer read 125 degrees F! I am not sure how accurate this is, as I used my oven thermometer, and the metal may have heated more than the air temperature actually was, but I plan on getting a real thermometer tomorrow, so we'll see. I would not be surprised if it does get over 100 degrees F.
Saturday, September 13, 2008
We all love to go to 'wild' places to relax, go hiking or camping, go out on a boat, or to the beach. However, there are very few places that have not felt the presence of humans in one form or another. It's always dishearting to me to go to the beach and see something like this... But what is worse is seeing the people hanging out on the beach as if this is a normal or natural state of affairs. They place their beach blankets in between piles of trash and let their kids run around. Why aren't they upset? What will their kids grow up to think?
We have a responsibility in keeping these places clean. It does not matter whose mess it is or whose fault it is, we all use these places... so we need to give back to them. That's why next Saturday, I am participating in the international beach clean-up. For more about that visit here. Do you know where your nearest clean-up is? There are always some clean-ups around, if you look, or you can always take the initiative yourself. The next time you visit your favorite spot, pick up five pieces of trash, as a way of 'paying back' for the time you spent there.
Thursday, September 11, 2008
This is a creosote bush, Larrea tridentata, that I saw on my first trip to Joshua Tree National Park with my wetlands class. We had gone to see the desert riparian habitat, but stopped off at this creosote patch, as I had never seen them before and was interested in seeing them up close.
They grow in discrete patches... originally it was thought that the compounds they produce kept other seeds from germinating. Now it is known that it is not chemicals, but their superior water gathering skills. There is no water around them to allow for a seed to germinate, they suck it all up!
The compounds that they produce inhibits digestion of the leaves and keeps it from being grazed by too many creatures, although there are some insects which have evolved to deal with the toxins (the creosote katydid and grasshopper). The leaves themselves are able to retain water, as they are thick and waxy. The creosote bush has been known to survive for 2 years without water.
There are three distinct populations of creosote bushes, and while they all share the same scientific name, they are genetically very different. The Chihuahuan desert population (western Texas and also in South America) has 26 chromosomes (2n), and is the founding population for the other two populations. The Sonoran desert population (Arizona) has 52 chromosomes (4n), and the Mojave desert population (California) has 78 chromosomes (6n). The Mojave population is the newest population, only coming into the area a little less than 11-12,000 years ago.
Sunday, September 7, 2008
Mark your calenders for September the 20th for the international coastal clean-up day! On this day, people from around the world will gather and clean up their waterways. Don't live by an ocean? There are clean-ups hosted for creeks, streams, ponds... basically any body of water!
If you want to register online to find out where the clean up closest to you is being held, click here. If you want to contact the clean-up coordinators on your own, there is a list of them here for the US and here for the rest of the world. If there is no clean-up in your area, you can become the host for a clean-up.
This is a great opportunity to help clean-up an area which we all love and cherish, as well as take part in collecting important data on the types and number of trash found around our waterways.
Saturday, September 6, 2008
When I think of strings, I think of the spaghetti worm. This worm lives in mucus tubes surrounded by rocks or sand generally in the intertidal areas and uses its thin white tentacles to gather food. The tentacles for a worm this small would probably be a little under a foot in length, while a worm with a body length of a foot will have tentacles about 3 feet in length. The tentacles themselves have a little groove filled with cilia (hair-like structures), that are used to move food particle from the sea floor to the mouth.
As an added bonus, you can also see a string of nudibranch eggs (the thick white wavy line to the right of the worm).
Friday, September 5, 2008
The food is similar too, although I use a lot of carrots, because she seems to eat them more than the other foods I've tried (mainly apples and cucumbers). Because it's so similar, there is no obvious reason why she should have felt comfortable enough to lay eggs... My hypothesis is that I put the enclosure in the sun for a couple of hours every other day, to give the plants sunlight. It makes the sand get pretty hot, but since she is a desert beetle I figured she could take it. Maybe the heat helped convince her to lay eggs, or at least helped the eggs hatch into larvae.
So, she will be in the bug guy's care for a week, and he is hoping to see the egg laying behaviour we observed, as well as find out if and what the larvae are feeding on... Of course now I am super nervous about getting the larvae to pupate!
Thursday, September 4, 2008
I've already posted a picture of Stumpy, my death-feigning beetle, But I had to post another one to celebrate the cool thing I discovered yesterday. The death-feigning beetle (Cryptoglossa verrucosa) is also called the iron clad beetle for its armor-like appearance. They are found in the deserts of the south west (California, Arizona, and the like), and are able to get all of their water from their food.
I obtained Stumpy and a friend from a bug fair last may, and named her Stumpy because she is missing the tarsus (or tip) of her right front leg. Her companion died about a week and a half after bringing them home. Since then, I've been half-hoping that some of the interesting behaviors that I witnessed when the companion was around were mating behaviors, but did not expect too much since months had passed.
Low and behold, when I checked her tank the other day I found this....
A cute little beetle larva! She had been burying her abdomen in the sand a few weeks earlier (which prompted me to start calling her a girl), and now I have confirmation of several of my hypothesis. She is a girl, the burying the abdomen in the sand was probably 'ovipositing' behaviour and she had stored sperm either from her companion or from when I got her! Cool! It's a bit nerve-wracking since the people I know who care for these guys have never had young before, so I hope some of them survive!
Wednesday, September 3, 2008
They have a lot of tropical fish, inverts (like the upside-down jellies pictured above), and, of course, a seahorse breeding program. Like most aquariums, they also have a touch tank, one for rays and one for inverts, which holds horseshoe crabs and conches among other things.
Across the street, in another building you have the rehabilitation center. Here you can check out some critters who are being fixed up for re-release, and some who are permanent residents. When I went, they had some turtle hatchlings which were very cute, but hard to take a picture of because they were so active! The rehabilitation center has a lot of signage posted about the animals that they have, and what particular ailment brought them there.
The aquarium portion is a medium-sized facility, which could capitalize on the research aspect more. They do have some signage talking about what research they do, especially for the sea horses and shark tagging, but you don't really get to see what's going on. The price is a bit pricey at $17 for adults and $12 for kids, however they are AZA, so if you have a membership to another AZA institution you may be able to get in for free or half off.
Is it worth the price of admission? YES!
Did I forget to mention that they have the only giant squid displayed in the USA...