Getting ready to participate in the PACE Workshop: Linking Paleoecology and Community Ecology! This is an NSF-funded workshop, led by Jacquelyn Gill and Brian McGill from the University of Maine, and Jack Williams from the University of Wisconsin. This workshop brings together paleoecologists and population and community ecologists to build capacity in addressing cutting-edge questions in ecology that would be better advanced by a cross-disciplinary perspective- should be fun!
Now that Juliana’s experiment is finished (for now, a second one is coming), lab work starts. There are several analyses that Juliana needs to run on her samples to be able to understand how light availability affects food webs and energy pathways. On the right, Juliana and I very focused on sorting invertebrates for community and stable isotope analyses!
Now it is time to start our sampling of urban bromeliads! Because urban bromeliads are exposed to increased temperatures and pollution, we want to explore their invertebrate diversity and stoichiometry. Bromeliads are commonly planted in public and particular gardens all around Brazilian cities because of their great beauty, which provides a great opportunity to study the dynamics of these systems in urban centers.
We know that in natural areas bromeliads host a large diversity of invertebrates, but we don’t know much about the organisms living in urban bromeliads. Because bromeliads are container-inhabiting mosquitoes (and many other invertebrate species) we decided to sample bromeliads in Petropolis, a city north of Rio, which is also known as The Imperial City in honour to the last Emperor of Brazil (Pedro II). Here is Vinicius and Juliana sampling bromeliads in an urban park in Petropolis. After this sampling, we come back to Rio with our “combi” full of bromeliads, which were used by Vinicius student, Nicholas Marino in a experiment focused on modelling water dynamics in the tanks of bromeliads.
After Petropolis, we sampled bromeliads in Rio do Janeiro. Within Petropolis and Rio we find some areas that are more urbanized than others, and this could help us to understand the community structure and the stoichiometry of these aquatic systems along gradients of urbanization. On the left, you can see Vinicius and Juliana sampling invertebrates in a “Carioca” Bromeliad.
After identifying the invertebrate species we find in these systems, we will run chemical analyses on bromeliad tissue, tank water, litter, and invertebrates! See how green is the water of these bromeliads, although you cannot see it in the picture, many of these bottles are full of mosquito larvae.
I am very excited about what could potentially be living (beside mosquitoes) in these miniature ecosystems! We will know very soon…
We just started another exciting field season, this time in Brazil. Juliana S. Leal (PhD student at UFRJ), co-advised by Vinicius Farjalla and Angélica L. González, is taking down her five month-long big experiment, and we are here to help her! Juliana used tank bromeliads as model systems to test the relative importance of autochthonous (primary production) and allochthonous (litter) energy sources to aquatic ecosystems. She manipulated the amount of light bromeliads receive, resulting (we hope!) in photoinhibition or photostimulation of primary production. She will measure responses in the amount of periphyton and filamentous algae produced inside the bromeliad tanks, the decomposition of organic matter, and through the use of stable isotope analyses, she will also determine energy pathways (i.e., autochthonous vs. allochthonous) for the aquatic food webs inhabiting these aquatic microcosms.
Bem-vindo ao Brasil! We started this field trip with a cold beer to cope the heat (~34 Celsius). The initial team is composed by an amazing and fun group of researchers from the “Laboratório de Limnologia, UFRJ.” The ladies in the picture, from left to right are Dr. Aliny Pires, Dr. Lucia Sanches, student Sorana Lima, and Juliana. After this super friendly welcome, I have no doubt that I will have a lot of fun with them.
Juliana’s experiment includes 12 light treatments x 4 replicates in the field (48 experimental units). She performed her experiment in the Reserva Ecológica de Guapiaçu (Regua), which is a beautiful nature reserve of Atlantic forest.
Juliana built mesh cover structures of different density to manipulate incoming light to bromeliads. After running this experiment for five month and allowing insect colonization, we are taking it down! We started collecting samples of water for chemical analyses, algae and periphyton for primary production estimates and stable isotope analyses. Look at Juliana (left picture) pipetting water from one of her treatments in the field.
Back in the lab, there is so much more to do. Juliana (bottom picture) is preparing water samples for water analyses. The picture at the right shows the wide variety of colours in the filters evidencing elemental residues found in the water. These will need to be analyzed for C, N and P contents.
Invertebrate sorting takes a lot of time and patience. We need to separate the invertebrates belonging to each treatment for identification, counting, weighing and stable isotope analyses. Below you see student Natalia Souza going over bromeliad water getting and classifying the invertebrates she finds.
Our work goes on until very late, no matter how strong is the thunder storm over us! Vinicius and student Carlos Batista joined us, and appear in this picture with Aliny measuring and washing a bromeliad to get its water volume capacity (a proxy for habitat size) and make sure we extracted all invertebrates. This is just the second day and we have only done 25% of the field work planned, another hard but fun day of work is waiting for us tomorrow, or I should say, in a few hours.
This week, about 40 researchers from several places of the world met in Paraty, Brazil to discuss the ecology of bromeliad ecosystems. We had intense and productive days of talks and discussions about topics that range from the critical maximum temperatures of invertebrates inhabiting bromeliads to the effects of drought on aquatic insects communities. It has been a GREAT week, where all of us learned a lot in a very friendly environment that involved several faculty, Postdocs, Ph.D students and Master students from different laboratories. The idea behind The Bromeliad Working Group is to join forces in collaborative projects along Central and South America to test ecological theory using bromeliad systems as study models. These studies can be done investigating and manipulating single bromeliads or a group of bromeliads in a local site to multiple sites in a regional scale.
I just came back from an exciting trip to the Atacama desert where I worked with a group of paleoecologists led by Dr. Claudio Latorre to collecting fossil rodent middens. Dr. Latorre and I are starting to investigate changes in the soil food webs in the Atacama during the last 50,000. Rodent middens represent important paleoecological records for arid regions of the world. In particular, Abrocoma and Phyllotis middens in South America (Atacama Desert, Chile) have provided unique spatial and temporal information about long-term ecological and climatic changes in arid and semi-arid environments. Plant macrofossils preserved in the faecal pellets of these rodent middens present high taxonomic resolution data, and together with radiocarbon dating, have been used as records of paleoclimatological and vegetational changes. Further, these rodent middens have been used as refuges by a high diversity of taxa and represent ecological evidence of soil arthropod communities inhabiting the rodent middens spanning from 50,000 years ago till present. Soil communities from rodent middens can be very useful for making inferences about the effect of past and ongoing environmental conditions on arthropod diversity and food web structure.
The picture on above shows a typical paleomidden, which are waste piles that packrats construct out of fecal matter and urine. Urine dries and crystalize trapping plant remains and dead invertebrates. The picture on the right shows a leaf-eared mice (Phyllotis sp), one of the two species responsible for the middens in the Atacama.
The last month has been filled with many new experiences and fun times. The five of us started out in Crucita which is in the dry coastal region of Ecuador. We began sampling in Portoviejo, an area not too far from Crucita. Each of the sampling areas offers a different unique ecosystem that greatly vary in the vegetation and insect diversity. A big indicator of being in the dry forest area of Ecuador are the large trees of the species Ceiba trichistandra (picture below). They are found only in dry tropical forests of the Pacific regions of Ecuador and Peru, and are just beautiful. In the wet areas that receive vast amounts of precipitation the vegetation is a dense wall of green and full of life.
I specifically enjoyed the night walks through the forest, one of which took place in the wet area of Rio Palenque. It seemed like all of the cool animals came out at night, ranging from large pseudo scorpions to tiny frogs. We even came across a couple of animals that lit up the forest on their own by using bioluminescence. The click beetle has two spots on each side of their head that light up, and the lightening bug’s abdomen, much like the ones in North America, shine bright. What the tropical forests lack in light, they make up for with sounds. There were constant chirps, buzzes, and calls from amphibians, insects, and bats that were incredibly different from the sounds heard during the day, which primarily came from birds.
As much fun as the night walks were work had to be done, which for me was sampling insects and spiders. I sampled multiple sites in order to gather preliminary data for my master’s thesis, which will look at the network structure change along an elevation gradient. To find the insects I have been using visual, sweeping, and black light techniques. Each technique has bias towards certain groups of insects, which makes it important to employ as many techniques as possible. The visual method is geared towards finding larger insects that are slower moving, whereas the sweeping method collects flying, and faster moving insects in the vegetation and air. The black light method enables the collection of many nocturnal insects, and has by far allowed for the most diverse collection. In order to gather spiders I visually locate the webs and collect those using vials. After collecting and sorting insects/spiders by order, and if possible family level, we are going to analyze their nutrient composition (nitrogen & phosphorus). I’m already looking forward to next year when I’ll be doing more in-depth sampling of spiders and insects in the Andean region!
One of the things that I enjoy the most while doing field work in the jungle is to do field work at night. Spiders and many other creatures become more active at night time, therefore to understand patterns of spider web building and prey capture we do a lot of our work after the sunset. In addition to working at night to get the data we need, night time provides a glimpse into the nocturnal wildlife. Believe me, there is nothing quite like walking the trails in the dark jungle with the fluttering moths and flies around our headlamps. This is one of my favourite moments here in the Amazon.
Our group had a night of adventure walking through the dark and muddy trails of Jatun Sacha observing and enjoying the liveness of the jungle. Although we knew (more or less) what was waiting for us on the trails, we were no shy expressing our excitement for the different animals we found. Along our way, we contemplated all sorts of creatures, most of them larger in size than expected or seen by us before, such as this spiny bush cricket of more than 10 cm long or this whip spider, also known as tailless whip scorpion that was the size of Philippe’s hand.
We were also fortunate to discover several small tree frogs in the dark; these animals spend a major portion of its lifespan in trees feeding on insects.
And Tiffany was never scared to grab any amphibian she found along the way, including this big and fat toad who posed with almost everyone for a good picture. As I said, she never doubted in capturing amphibians to look at them closer, the picture on the right shows her manipulating a caecilian, a tropical amphibian that look like a large worm or a slick snake that we found two days earlier at Palenque in the cloud forest.
Beautiful insects such as this dragonfly are very common to observe as well. However, the jungle would not be the jungle without spiders, and we looked at several interesting species waiting in their webs for a prey. For example, these araneas, which build a beautiful orb web.The most amazing spider we found however, is this net-casting spider, which uses a blue/purple web that suspends between the front legs. This spider prey capture strategy is to stretching the net and propel itself onto the prey, entangling it in the web.
Army ants are also common to find in the jungle at day or at night. Here we followed the line of ants to find their nest, a scary hole in the base of a log where all the family reunites; thousand of ants! After a two hour walk and happy for the experience we had, we finish our night and went sleep under our mosquito net beds.
Field work in the jungle is a very intense experience; this is a hostile work environment, which in part you could fight by using one of these creative tennis rackets that deliver an electric shock to kill flying insects (in here there are tons of them). According to those who have used these gadgets, if you touch the mosquito with any part of the racket face during your swing, then … POW! This device may be very handy for those of us who are attractors of mosquitoes and suffer from their bites, especially in those areas where Dengue and currently Chikungunya are infecting hundreds or thousand of people. Chikungunya (first medical description was in Tanzania in the 1950s) is a relatively recent virus disease in America, transmitted by the same mosquitoes that Dengue. For our bad luck, both of these infectious diseases are present in our study areas; hopefully none of us will get infected this field season.
But working in the jungle is so exciting that you do not worry too much about mosquitoes and other annoying bugs, the heat, and the overwhelming humidity. The jungle offers us an unique diversity of life forms. Like this fellow Llama was observing us while we were collecting spiders from nests beside the highway in the mountains of Ecuador.
And what about this beautiful Masket Trogon (female), a fairly common bird of the humid highland forests in SouthAmerica; its beautiful colours catched our camera lenses.
But our real target were spider nests, and we found many of the different social and sub-social species that live in the East of the Ecuatorian Andes. For example this Anelosimus baeza nest in the picture at the left. Spiders are fascinating study systems and they build such a beautiful webs, the energy investment is very high, not just in the process of building but also in the material (silk) they need to produce to build a functional web. The interesting thing is that these webs caught nutrients (prey) and are also made of these nutrients. In the picture at the left you see Mark (Master student in the Avilés lab at UBC) looking for spiders within a beautiful spider nest. Mark will be studying how precipitation and predation pressure by ants and waps may affect the proportion of spider webs of different architecture: orb webs (2-dimensional webs), tangle webs, and sheet and tangle webs (3-dimensional webs).
The world of species interactions is fascinating; it is not just the excitement of knowing how natural communities are structured in terms of who eats whom. Some other ecological interactions are also very interesting and important in natural communities, for example some parasitoids can cause changes in the behaviour of their hosts. The picture on the right shows a parasitoid wasp that infected a spider. These parasitoids make their spider hosts build a modified web that protects the parasitoid larva while developing, amazing, right?
In our trip looking for spider nest there was a lot of climbing, and Philippe (Master student in the Avilés lab at UBC) is the expert in this sort of activities! You can see him in the picture on the left checking a social spider nest in a slope at the edge of the road. However, Phil was not the only one climbing hills, Leticia (PI, UBC) also did her part to take a closer look to the nests and collect some spiders, and of course I also climbed to record all these activities.
Our trip continued to Jatun Sacha and in our way we were all amaze by the astonishing view of the Sumaco, a symmetrical volcano that appeared on top of the fog covering the high elevation cloud forest. Sumaco latest eruption was about 100 years ago.
While part of the local team was sorting the research permits at the Ministery, picking up some extra malaise traps (flying insect traps) at the university, checking on the field vehicle that is getting fixed, etc. some of us took advantage of our time here and did some tourism in the city. We walked up to the Pichincha volcano, which is at more than 15,000 ft. The day was beautiful and we had an amazing view of Quito city. The landscape walking up to the mountain is gorgeous, but you feel the effects of the altitude with every step.
For those that do not want to walk up, there are horses to rent, but we as good outdoor people decided just to walk up…as far as our breath and fast beating hearts allowed us! We ended doing a very good job beside the altitude sickness we felt.
Along our way, we were lucky to see this couple of carunculated caracaca, a bird of prey typical from the Andes of Ecuador and Colombia. These two were hanging around a few meters from us, probably expecting us to feed them.
We also had the chance to see llamas, one of the four SouthAmerican Camelids. As you can see, nor Tiffany (González lab) or Katrina (Avilés lab) could resist the opportunity to be kissed by Linda, a cute white llama.
This is part of the crew that did a great job scouting for study sites in West Ecuador (from left to right: Luis (soon starting his PhD at UBC in the Avilés lab), Jen (Postdoc in the Avilés lab), Mark (Master student in the Avilés lab), Leticia Avilés (PI, UBC), and me (PI, Rutgers University), but I am behind the camera. Our goal was to find good study sites along a precipitation/productivity gradient. The idea is to study: (1) Whether precipitation and predation intensity (by ants and wasps) affect the abundance of spiders building different web architectures (Marks’ Master thesis); (2) Insect abundance and body size (spider prey) patterns along this gradient (Katrina, meet her in the picture below). We will also do some chemical analyses of insects to see if prey quality for spiders varies along this gradient (Tiffany, meet her in the picture below); and (3) Determine why are there no social Anelosimus species in the dry coastal areas of Ecuador (Jen).
Meet Sam, Tiffany, and Katrina (from left to right). Sam comes from Wisconsin; she will start her Masters at UBC this fall. Katrina comes from beautiful Vancouver and this summer she will work on her honours thesis; both Sam and Katrina belong to the Avilés lab. Tiffany recently joined the González lab, and she will get involved helping in several projects in the coast. Tiffany will also get trained in field work techniques studying spiders and insects. Next year, she will be focused on her own research!
And the last but not least member of the team is Phillipe! Phil is Quebecua (French Canadian) and he is another of Leticia’s master students. Phil is working on ecological networks of arthropods associated to social and sub-social spiders…a very interesting project.
Here we are at El Pobre Diablo, which is a popular restaurant/jazz bar in Quito. We all (as usual, I am behind the camera) had fun enjoying a nice chat and a delicious meal.