Wednesday, December 1, 2010

Cranes in the marsh

I spent a lot of time on I-95 this Thanksgiving weekend. A lot of time. However, in the throng of grumpy travellers, there was a happy sight for which I was thankful. And this small delight came when I least expected it - when traversing the badly degraded Hackensack Meadowlands, which is generally, for me, a mournful crossing. The sight: cranes on the marsh. Not avian cranes!

There is a massive restoration taking place on the Richard Kane Wetlands, where the Meadowlands Conservation Trust and EarthMark Mitigation Services are removing invasive Phragmites, reconnecting tidal creeks, and planting salt marsh grasses on >200 acres of brackish marsh. The area is large - the photo below (a good one, no? I was pleased with it.) does not capture the full area being restored. This work is financed as a "mitigation bank" - companies or agents (in this case, mostly transportation agencies) degrading or destroying wetlands in other places compensate by paying for the restoration improvements. It is positive that this approach can fund truly large scale restoration efforts. However, these positive advances come at the cost of continued wetland degradation and destruction elsewhere. Is this tradeoff the best option for funding restorations?

Friday, November 5, 2010

Eaten to death: salt marshes in Cape Cod

Eric Van Arsdale, a senior at Brown University working with my graduate advisor Mark Bertness, published an excellent op-ed in the Cape Cod times about salt marsh die-off, which is caused by runaway consumption of marsh grass by the nocturnal squareback marsh crab, Sesarma reticulatum. In his article, Eric mentioned a cool You-Tube video of the crab's nighttime activities that I'm re-posting here.

Tuesday, October 26, 2010

Travels to the South and the North

I've been traveling these past two weeks, first to a TNC workshop in lovely Sanibel Island, Florida, and then to the equally lovely city of Chicago, where I met the other Smith Fellows for a retreat at the Lincoln Park Zoo (LPZ).

Appropriately, we spent the majority of our time at the LPZ in the Great Ape House, where we saw an experiment examining taste preference in chimpanzees. A false termite mound in the chimp enclosure is seeded with different sauces - peanut butter, bbq, ketchup, vinegar - and the scientists can do taste tests to see what flavors chimps prefer, and how the social structure of the chimp group affects an individual's access to condiment resources.

The chimpanzees use sticks to access the condiments, and we saw what zoo intern (a term which does her extensive knowledge and experience no justice) Kathy described as "the most explicit demonstration of tool sharing [she] had ever witnessed," when a crafty adolescent female chimp, coaxed by submissive smiles and an outstretched palm, passed her stick to her mother. How I failed to get this momentous instant on camera is completely beside me.

Instead, here are a few photos of the Ding Darling National Wildlife Refuge in Sanibel, where I cleverly brought my camera.

Tuesday, September 14, 2010


I was hanging with the folks from the Invasions Lab at SERC today, and it reminded me of several photos that I took in the Boqueria in Barcelona, an open-air food market with a heck of a seafood selection. In with the medley of clams, snails, and squid, there was even a green crab (invasive in the northeastern U.S., among other places) - no doubt, an accidental tourist.

Thursday, August 19, 2010

Around the lab at SERC

This year, I've moved my home (to Washington, DC), my job (to Smithsonian Environmental Research Center), and my field sites (to the Chesapeake Bay), with many of opportunities to see coastal mid-Atlantic flora and fauna. Maryland and the Chesapeake Bay are rich with life - here are a few photos. (Of course, I've yet to catch on camera many good sightings - blue-tailed skinks, great blue herons, bald eagles, swallowtail butterflies, luna moths, and watersnakes, to name a few. More photos will come later!)

Saturday, July 3, 2010

Mi casa es su casa, caterpillar

I saw these house-building caterpillars last week outside of my office at SERC in Edgewater, MD. Anyone know the species? I will rear a few out to adults to figure it out. I'll post here if I can figure it out. Please let me know or post a comment if you recognize it!

UPDATE July 7, 2010: Dean Janiak helped me find it on - It's a bagworm moth, genus Thyridopteryx!

Tuesday, June 22, 2010

Experimental validation!

In March 2009, maritima published a recommendation for mangrove restorations that Brian Silliman and I wrote about in Ambio. We suggested that mangrove seedlings be planted in high densities clumps to reduce the harsh physical stress (anoxia and high salinity) of the intertidal environment, which can be lethal to mangrove seedlings. Both theory and experiments suggest that mangrove plants, ecosystem engineers that are capable of oxygenating the mucky forest floors of mangrove swamps, would respond well to being planted closer together, where they might facilitate each others' survival (i.e. positive density dependence).

Now, Mark Huxham and colleagues have shown that seedlings do survive better when planted at higher densities in field experiments! Their study appears in the July 12 issue of Philosophical Transactions of the Royal Society B: Biological Sciences. They found higher survival at higher density for the species Rhizophora mucronata at a low intertidal site in Sri Lanka and for the species Avicennia marina at a high intertidal site in Kenya.

Tuesday, June 1, 2010

Renaissance Keryn

This is not a Renaissance reenactment, but rather my graduation ceremony at Brown University this Memorial Day weekend. It's official...I'm Dr. Gedan.

Thursday, March 4, 2010

Tweetable: "Seas the Day!"

On Tuesday night, Jane Lubchenco, marine ecologist and current NOAA Director, gave the 11th Annual Roger Revelle Lecture, sponsored by the National Resource Council Ocean Studies Board to honor namesake Roger Revelle, who discovered that the oceans will not absorb limitless carbon dioxide from fossil fuel burning.

It seems that these days we are increasingly realizing the limits of the ocean, as we approach them from many different angles - the limits of fish harvest, the limits of nutrient transformations and oxygen availability, and the limits of stability of ocean pH, salinity, and temperature. Dr. Lubchenco spoke of these challenges. Local and global solutions, she said, must be pursued simultaneously. Controlling local degradation from nutrient pollution and over-fishing, for example, will help to avoid unpredictable and potentially difficult interactions between local and global stressors and maintain overall system resilience. She ended her lecture hopefully, discussing new approaches to data collection, data synthesis, and environmental regulation that will help us address problems before we reach tipping points and advising us to:
"Seas the Day!"
which is a quote that, if I were a Twitterer, I'd call downright tweetable.

Monday, February 8, 2010

unsung victims of the DC Snowpocalypse

The +2' of snow that hit DC this weekend has surprised and wreaked havoc on many. For example, the federal government, city schools and universities, and many other businesses have been closed over the weekend, Monday, and Tuesday, at a significant economic loss (partially recovered in sales of snow shovels and hot chocolate?). But the unsung victims in this storm, in my opinion, are the Washington street trees.

As the snow started to accumulate on Friday night, I heard a loud *crack* in the courtyard of my building, and saw the first fallen branch. A large branch from an >80 year old tree had smashed another small tree below it. Several other trees in my courtyard also lost large branches, bending and breaking under the weight of 26" of wet snow. Walking the city streets, I saw other casualties.

A few years ago in Providence, RI, they had a tree tally, where volunteers (including me!) identified and counted the street trees for a public record. (There are nearly 25k street trees in Providence, in case you were wondering.) I haven't found such a dataset for DC, although there is a city Urban Forestry Administration. Beyond my anecdotes, it'd be interesting to know the scale of the damage to the city's trees from Snowpocalypse 2010.

Tuesday, February 2, 2010

winter in the intertidal

I was out in the sub-freezing weather in Rhode Island this weekend to set up succession plots and settlement plates to measure barnacle recruitment, which has already begun! (See a slideshow of last year's recruits here.) There's nothing like seawater freezing on your double-gloved hands to make you feel alive!

I expected the rocky intertidal fauna that had the option to ride out the extreme cold buried in the mud, but I was surprised to see many of the mobile critters out and about during the extreme low tides (-0.5 m or -1.6 ft, nearly 0.5 m lower than the predicted low tide, probably due to wind). Seastars were remarkably abundant, and I also saw a lady crab, Ovalipes ocellatus, a swimming crab that I rarely find in the intertidal (the Kunkel lab at UMass Amherst has a good lady crab photo here).



Thursday, January 21, 2010

science the searchlight

I am teaching Environmental Science at American University this spring, and in class today we discussed Aldo Leopold's Sand County Almanac. This quote spoke to me:
"We see repeated the same basic paradoxes: Man the conqueror versus man the biotic citizen; science the sharpener of his sword versus science the searchlight of his universe; land the slave and servant versus land the collective organism."
To me, the concept of "science as sword versus searchlight" pertains to the use of technology to degrade versus restore the environment. However, I think the metaphor also suggests science as a path to enlightenment.

This little light o' mine...I'm gonna let it shine. Let it shine, let it shine, let it shine....