Isle Royale is a National Park and is sometimes referred to as a ‘wilderness preserve’. It’s been famous as a laboratory of natural predation as the careful study of the relationship of the island’s wolves and moose has been underway for more than 50 years. It is the largest island in the greatest body of fresh water in the world. The largest lake on the largest island in the largest body of fresh water in the world was named Siskiwit by the Chippewa. Samples from the bottom of Siskiwit Lake were recovered by scuba divers in September of 1980. Part of an atmospheric deposition study undertaken by Dr. Phil Gschwend, the analysis of these unusual cores caught the attention of a new Post-Doc at WHOI. Chris Reddy was determined to return to Siskiwit to resample [core] this unblemished lake-bottom for his own research interests:
[excerpts from]
APPLICATION FOR A RESOURCE ACTIVITY PERMIT
Name: Christopher Reddy, Ph.D. and Timothy Eglinton, Ph.D.
Institution: Woods Hole Oceanographic Institution (WHOI), Woods Hole, MA 02543
Project title: Sedimentary Records of Pyrogenic Polycyclic Aromatic Hydrocarbon Emissions from Fossil Fuel and Biomass Sources.
The objective of this expedition is to measure the molecular-level carbon-14 content of pyrogenic polycyclic aromatic hydrocarbons (PAH) in the sediments of Lake Siskiwit. PAH are a class of highly toxic organic contaminants that are either found in fossil fuels or are formed when fossil fuels or vegetation (biomass) are combusted. Because of the pristine nature of Lake Siskiwit, the PAH in its sediments should only be from atmospheric fallout of pyrogenic PAH and not from spilled or leaked fossil fuels. Hence, Lake Siskiwit is an ideal location to investigate the historical inputs of pyrogenic PAH to the environment ... we plan to collect sediment cores from central Siskiwit Lake (see map) from the sediment surface to a depth of 50 cm (equivalent to the pre-industrial period of ~1800). From each 5-cm interval, we will measure the carbon-14 in the PAH. For each interval, we will need approximately 1 to 2 kg of sediment. This quantity of sediment cannot be obtained with a sediment push-core because of the low abundance of carbon-14 in PAH, but instead a boxcore, with a ~1m2 footprint, must be used. The boxcore will be deployed from the research catamaran LADAS (see attached figure) with a hand-powered winch. Because of (a) the mass of the boxcore and the sediment within and (b) the water depth (~120 feet) of the sediment where we plan to sample...
... it is imperative that we use a very steady platform that the LADAS [Laser Slope Gauge/Acoustic Doppler Current Profiler/Anemometry Package/Surface Sampler]
provides. A rowboat or similar vessel will not be safe or efficient. The LADAS is portable and lightweight and takes the space of about three canoes when dissembled. We plan to bring the disassembled LADAS to Grand Portage and be ferried to Malone Bay, where we will hand-carry the pieces of the LADAS to the edge of Siskiwit Lake. There, we plan to assemble the LADAS and set-up camp...
The story of mud, muscle and moose follows...
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