Hidden Herbivores

When thinking about plant-herbivore interactions, it is important to remember that not all damage caused to plants by herbivorous insects is immediately obvious. In fact, the majority of herbivory on plants (and the most damaging) is often caused by insects which cannot immediately be seen. Many types of insects live almost their entire lives inside a plant, emerging only as adults in order to find a mate. This can result in entire food chains (also involving predators and parasites) being enclosed within a single stem, leaf, or root, and can make them particularly interesting to study due to the closed nature of the system.

Ganesh collecting galled stems at the native Rappahannock River site

In Phragmites australis, some internally feeding insects induce growth abnormalities in the stem, known as galls. Symptoms of galls are easily recognisable in the field (once you know what to look for), characterised by shortening and swelling of the stem near its tip, and the death of the top leaf (see below). During our summer research trips we collected around 100 stems per site, from a variety of both native and invasive Phragmites sites throughout the United States. We kept these stems on ice and once back at LSU stored the stems in a freezer to preserve the insects inside them.

Galled stems being readied for dissection by removing leaf sheaths

Stems were prepared for dissection by removing leaf sheaths and were then dissected using a splitting tool by cutting the stem from the bottom to the top, examining its inner space for any kind of insect or arthropod species. All organisms found were grouped into a particular recognisable taxonomic unit (RTU - visually distinct species) for each site and stored in vials of 96% ethanol for preservation. We also recorded on a data sheet exactly what we found in each stem and any other relevant information.

The dissection station

So over the course of this past semester, Randee (one of the undergraduate students working our lab) and I dissected a total of 2025 stems. It was a lot of repetitive work and hours under the microscope. Each type of insect we found would be given a funny name for future identification such as "narrow white guy", "claw worm", "orange pupae", "emerging wasp", and "boring brown mite", and we also photographed each new type of insect we found. In total we collected around 240 arthropod samples.

Lipara sp. with inquiline

The organisms which actually cause the galls are fly larvae (immature stage) from a genus called Lipara, of which there are a number of species: Lipara pullitarsis, Lipara rufitarsis, Lipara similis, and Lipara lucens). Three of these are established in the United States. Lipara similis is one of these species, and is easy to identify thanks to the dark colouration at both ends of its body (see picture below). Lipara pullitarsis and Lipara rufitarsis are also established (see picture above), but distinguishing between these two species as larvae is very difficult. Larvae of other insect species can also be found living inside the galls with the Lipara. These are commonly known as inquilines, and while some have no negative effects on the Lipara, some can be predatory or parasitic.

Lipara similis

The next step in this project will be to finalise sorting and identification of all of the insects collected. The identification process will be difficult, as it's notoriously hard to identify immature insects. Once identifications are complete, the data can be used to answer a number of interesting ecological questions. Some of the questions we are interested in is how community composition of the galls differs between invasive and native Phragmites, and also how it may vary with latitude. Results will be forthcoming in the next couple of months, and I'm looking forward to seeing if all our hard work collecting and dissecting stems has paid off. For now, enjoy some of the pictures of the hidden herbivores of Phragmites.

Small gall midge (Microlasioptera flexuosa)

Unidentified larvae and possible predator (top of photo)

Nice looking brown spider

A species of wasp pupating inside the stem

Unidentified larvae

Lipara sp. with inquiline pupae

Top 5 Albums of 2012

Some awesome music was released in 2012, and I've compiled a list of my five favourite records released this year - none of which you will be hearing on the radio anytime soon unfortunately. Check them out to hear the amazing stuff that true musical artists are creating by clicking on the link attached to each of my favourite tracks from each album!

Honourable Mentions:
Mono - For My Parents
Josh Varnedore - Sun Chapter
Jodis - Black Curtain
How to Dress Well - Total Loss
Cloudkicker - Fade
Lights Out Asia - Hy-Brasil

5. Almeeva - EP #2
Something a bit different that what I normally listen to, Almeeva is trancey, up-tempo music mostly created using traditional instruments, but with a minimalist idealism. The pulsing rhythm sections on this short EP of five songs really drive the music, complemented nicely by the spacey guitars. Looking forward to hearing more from Almeeva soon.

Favourite Track: Strobe

4. Hammock - Departure Songs
Almost a little disappointing by Hammock standards, it goes to show that even an average Hammock album is still so much better than almost any other music currently being released. There are 19 songs on this double album, which makes it a little too long for my tastes, but most of these songs are unbelievably good, with particular standouts being Cold Front, Tape Recorder, Dark Circles, and Ten Thousand Years Won't Save Your Life. This is Hammock's most ambitious album to date, with many songs breaking away from their traditional ambient approach, and much more utilization of percussion and rhythm guitars. It makes for a cathartic atmosphere in this album about loss, and the music video series directed by David Altobelli is a perfect companion. I'm looking forward to Hammock's next release which has been described as the complete anthithesis to this one.

Favourite Track: Cold Front


3. Helios - Moiety 
Keith Kenniff is an internationally recognised composer (whose music you have undoubtedly heard in films or advertising but never noticed), and Helios is just one of the many projects he is involved in. He generally takes a minimalist approach to writing music, but there is absolute beauty in the hypnotic and soothing compositions. The production is lush and cinematic, with post-modern piano often taking the forefront but supported by gorgeous guitar melodies and dense ambience  I must start checking out the rest of his back catalog soon, but first I have to digest Helios' latest release, a remix album featuring two of my other favourite artists - Hammock and Rhian Sheehan. I guarantee you will lose yourself in this music.

Favourite Track: Nothing It Can

2. Neurosis - Honor Found In Decay
The tenth studio album by post-metal giants Neurosis is monolithic. At its heaviest, the music represents an epic landslide, obliterating all in its path, while at its softest, the listener feels calm and at one with the cosmos. As is expected from Neurosis at this stage in their career, the musicianship and production is simply outstanding. The tribal drumming by Jason Roeder on songs such as At The Well, My Heart For Deliverance, and Casting Of The Ages is something which can be replicated by no other band, the vocal styles of Scott Kelly and Steve von Til complement each other perfectly, and the varied song structures used contribute hugely to the success of the album. Neurosis have always been a band which make you feel a part of something greater, but on Honor Found In Decay they take it to a whole new level.

Favourite Track: My Heart For Deliverance

1. Deftones - Koi No Yokan
Deftones are one of only a handful of bands I listened to ten years ago that I still listen to today. This is quite amazing considering how much my music tastes have changed since I was 15. Back then, the Deftones were my absolute band and not much has changed since then - I haven't stopped listening to this album since it was released on November 12! Koi No Yokan is a Japanese saying expressing a premonition of true love upon first meeting someone, and it aptly describes this album. The production is full and lush, and every band member is at the absolute top of his game, none more so than vocalist Chino Moreno and guitarist Stephen Carpenter. Every song on this breathtaking album is ultimately a supreme lesson in emotional groove and outstanding songwriting.

Favourite Track: Rosemary

Exciting albums coming in 2013:
Jakob - TBA
Tool - TBA
Rhian Sheehan - Stories From Elsewhere
*Shels - TBA
Palms - TBA

Halloween 2012

After spending Halloween weekend at New Orleans last year, I had to go back again. I went with my friends Fallon, Pradip, Bibek, and Whitney, with Whitney's Mum nice enough to let us stay at her house for the night. We had an epic night out on Bourbon Street, hanging around with the thousands of other people in costume!

The two zombies with Cheech and Chong before heading to downtown New Orleans

The usual chaos on Bourbon Street

With my labmate Anthony

Ecology Lab

This semester I'm teaching ecology lab for the first time since I've been at LSU. It is usually taken in conjunction with the fourth year ecology lecture course, taught by a number of professors (including my advisor, Jim). As a third or fourth year course, this lab is a bit of a step up in conceptual difficulty for the students, as well as requiring a fair amount of work for the minimal credit it is worth. The students have a high workload, with three full lab reports to write, three other assignments, and five quizzes during the semester (which makes a lot of marking for me to do). Still, it would have to be one of the most fun courses for both students and teachers at LSU, especially if you enjoy being outdoors.

The labs are three hours per week and each week has basically a similar structure with a short introductory lecture/discussion with the students before we head out to the field or work in the lab to collect data of some sort. Almost every week we aim to get out doing some sort of field work, as for most biologists (including myself) this is the best part of the job! So far we have been to cemeteries in Baton Rouge, gone fishing at streams on and off campus, been trekking through a swamp, and we will be measuring food web related data from lakes in Baton Rouge and sampling insects from various fields during the rest of the semester.

Seining for minnows at Foster Creek

Golden Silk Spider, or Banana Spider (Nephila clavipes)

So far we have been to a couple of really cool locations. For a lab on population growth we headed north to Port Hudson, an old civil war battle site now used for reenactments. There we sampled minnows in Foster Creek and used the mark-recapture technique to estimate population size. A really nice natural forest surrounded the creek and there was plenty of wildlife to be found. I saw an eastern diamondback rattlesnake, chipmunks, squirrels and a couple of large banana spiders (Nephila clavipes), a species of orb-web spider, the largest spider family on the planet along with tarantulas. The females of these species are around the size of a human hand while the males are tiny in comparison.They look scary, but their bite is harmless - it's the small spiders you really have to watch out for!

The other sweet place we have headed to do field work is the Bluebonnet Swamp, a patch of land in the middle of Baton Rouge which has been retained as a swamp park for recreation, containing walking trails and an education center. During two labs there we helped remove the invasive plant species elephant ear (Colocasia esculenta) from an area of the swamp where it is growing aggressively as part of a community service component of the course. The first week of this lab was made particularly interesting due to a downpour of rain making the swamp a lot more swampy than usual. Some students had more fun than others, with a couple falling into the water thanks to the muddy ground and hidden underwater branches and roots

In the process of passing this course the students get a good footing in a number of topics central to ecology, including population growth, measuring diversity, invasive species, food-web analysis, biogeography, scientific writing, and the all-important use of statistics. It is a really good course, and universities in New Zealand would certainly benefit from including advanced lab courses such as this in their programs, something which is generally lacking. I'm really enjoying the opportunity to teach it, and am looking forward to teaching it for the remainder of my time at LSU.

Students removing invasive elephant ear (Colocasia esculenta) in Bluebonnet Swamp

One of my classes for the semester

A Year In The USA

So I've now been in the USA for a little over a year, and it's been one hell of a ride so far. Time has simultaneously and inexplicably gone fast and slow at the same time. I've had a ton of great experiences  during the year I've been here (most of which I've blogged about), met a lot of new people, and traveled to so many awesome places. Most importantly though, I feel like I have made some significant progress towards my postgraduate degree and to becoming a better scientist, largely due to my advisor, Jim, along with other faculty members at LSU. My knowledge base of most areas of ecology has broadened considerably while adding crucial detail to many more specific subjects, as well as gaining more valuable practical experience - but there is still so much to learn and do before I graduate! I can't wait to see what the next year brings, but right now I'm most looking forward to heading home for Christmas and seeing all of my friends and family. I miss New Zealand and can't wait to see it again!

Waiting For Isaac

Hurricane Isaac hit the Gulf Coast of the United States about ten days ago, leaving areas flooded and people without power for days, forcing many people to evacuate their homes, and costing nine people their lives. We knew the storm was coming to the general Gulf Coast area at least a week before it hit but initial weather models had it going through Florida, so most people weren't too worried. However, during the week, the models kept pushing progressively westward as the tropical storm built in strength. Around three days from its arrival it made a large jump west, causing major alarm in Baton Rouge and Louisiana and prompting the declaration of a State Emergency. All of a sudden Walmart and other big grocery stores were flooded with people, getting all the bread, water, ice, canned food, batteries, candles, and most importantly - alcohol that they could buy. Liquor sales really shot through the roof thanks to the number of hurricane parties being thrown as school was cancelled for three whole days! Petrol stations had lines of cars bumper to bumper down the street, and people were driving all over the place like madmen. And as the storm drew closer it only got worse, as people evacuated New Orleans, the place expected to be worst hit (and exactly five years after hurricane Katrina), to come to Baton Rouge to further clog the roads and clean out the stores.

Hurricane Isaac around 12 hours before making landfall 

All of Monday we kept hearing the hurricane was going to arrive early Tuesday afternoon. Come Tuesday afternoon, the sky was still clear with just a little breeze; turned out the hurricane had unexpectedly stopped in the gulf, right as it approached New Orleans. We spent hours during Tuesday night watching TV, and gradually seeing the conditions in New Orleans and surrounding areas become worse and worse - reporters were struggling to stay on their feet and often had to stop reporting to shield their face when the rain became too hard. Thanks to the $14 billion spent on the levees large parts of the city suffered only minor damage, despite Isaac dumping more rain and tidal surge on NOLA than Katrina did!

The storm finally hit Baton Rouge early that Wednesday morning. We woke to some pretty strong wind and persistent rain, which had knocked over some pots outside our front door. After waiting so long for the storm to arrive we now all waited for it to gain in strength...but it never really got too intense. There were occasional strong gusts of wind, and a day of steady driving rain, but most of the city was unscathed, with just a few windblown branches and debris along with minor flooding. At one point we were so bored at sitting around inside we went for a walk around the neighborhood in the rain!

Around 5 pm of the day of the storm, the power went out (we were one of over 900,000 homes to be affected in Louisiana alone. We were well prepared so it was no big deal, and cooked on a gas stove that evening. We thought the power would be out for a day at most, but it ended up taking three days for it to be restored. We were really lucky it wasn't so hot during the rest of the week and the temperatures inside in the evenings were bearable even with the AC off.

So below I've posted a short video of the storm taken from the front door of my house. It was captured around 2:00 pm on August 29, when the storm was more or less at its most ferocious here. Football season is upon us here in Baton Rouge now, and all are expecting LSU to make another bid for the national championship. Let's hope it happens!

Back Down South

Following our New Jersey and Delaware sites, we blasted through our three sites in Maryland and Virginia with relative ease. But again I was stung by wasps, twice, at our Virginia site on the Rappahannock River. This time it was by a paper wasp, from the large nest which you can see in the photo below (I took the photo after I was stung). The stings from these hurt nowhere near as much as the one I got the previous day, and look nowhere as bad either. I wish I knew what sort of wasp it was that stung me at Estell Manor, but I only caught a fleeting glimpse of it as it buzzed away!

The paper wasps (Polistes sp.) which stung me!

We had Monday off as Tim, the Park Ranger at Mackay Island Wildlife Refuge, couldn't take us out in the boat until Tuesday. So we decided to go to Kitty Hawk, a small town in North Carolina, famous for being the the town right by the huge sand dunes where the Wright brothers performed the first controlled powered flight. The main attraction there was the memorial to the Wright brothers, which was pretty cool. It was situated on the actual site where they made their first flights, which were marked out by boulders. They made four flights on December 17, 1904; the first three just 37, 53, and 61 metres, respectively, but the final one was really impressive, at a whopping 260 metres! The memorial also had a nice museum with exact replicas of both their glider and plane which made the first flight. We also checked out what is supposedly the largest sand dune on the east coast, which was pretty cool, but had nothing on the dunes at Mason Bay on Stewart Island.

Hangliding off the top of the dune

The next day we were up at 5 am for an early start at Mackay Island, where we have three sites. We had been dreading this day since the start of the trip due to the waist deep marsh water in some places, high humidity and heat, and the strong possibility of close encounters with deadly and agressive cottonmouth snakes. As it turned out it was actually a pretty easy day. We didn't see any snakes, the weather was cool and the forecast thunderstorms stayed away. We stayed in a hotel literally right beside our final site in Georgetown, South Carolina, nailed that site early the next morning and then had a boring thirteen hour drive back home. So the trip was ultimately a success; some useful data was collected for all of our research projects, we arrived back in Baton Rouge two days earlier than planned, and I even managed to add another two states (West Virginia and Pennsylvania) to the list of those I have visited, bring the total now to 21. Classes start back at LSU on August 20, but before then we have our six sites in Louisiana left to do!