Monday, July 30, 2012

The 1956 Biological Reconnaissance of Middleton Island. Part 1: Marine Shells of Middleton Island, Alaska.

As mentioned in the previous blog entry, Middleton Island got the attention of science at a relatively early point in time. Due to its unique location and well preserved geological features, over the years the island attracted the attention of many geological researchers. Middleton Island, located near the margin of the continental shelf in the northern Gulf of Alaska, has emerged from the sea during several major episodes of co-seismic uplift of about 7 m, 8 m, 6 m, 9 m and 7.5 m, which are recorded by marine terraces. These uplifts have been dated at roughly 4,300, 3,800, 3,100, 2,390 and 1,350 radiocarbon years before present, respectively. The most recent uplift took place during the 1964 Alaska Earthquake, when on March 27 the whole island got lifted up another 3.5 m on average (Plafker & Rubin 1978).

In contrast with the geological interest the island has received during previous decades, the number of biological studies conducted on Middleton that have a clear relationship with the island is relatively small. Thus far the most important moment in the recorded natural history of Middleton took place in June 1956, when a field party consisting of Dr. Norman J. Wilimovsky (U.S. Fish and Wildlife Service), Dr. John H. Thomas (Stanford University) and Robert Rausch (Arctic Health Research Center, Public Health Service) undertook a biological reconnaissance of Middleton Island. Their visit had been arranged because of military activities on the island (at that time there was a large scale Cold War radar station under construction) were likely going to cause imminent disruption of the island’s natural relationships. This made it desirable to record as much as possible of the island’s natural history before the opportunity was lost. Their work was supported mainly by the Office of Naval Research and the United States Air Force, but additional support was provided by the Arctic Research Laboratory, Stanford University and the Arctic Health Research Center. These studies were aided by a contract between the Office of Naval Research, Department of the Navy, and the Arctic Institute of North America (Rausch 1958).
As far as I could see the 1956 biological reconnaissance resulted in three publications. Robert Rausch described the island’s avifauna in “The Condor” in 1958 and John Thomas published his story about the island’s vegetation in “Contributions of the Dudley Herbarium” in 1957. During their stay in 1956, the party also assembled a small collection of mollusks from the intertidal area, which had been submitted to the California Academy of Sciences for identification. Eventually G. Dallas Hanna and Leo George Hertlein identified the marine shells and these were listed and described in 1959 in “The Nautilus, The Pilsbry quarterly devoted to the interests of conchologists marine shells”.  

During my first stay on Middleton Island in 2005, however, I noticed that during recent decades little had been published about the general wildlife of the island and that the available works about the vegetation and avifauna (Thomas 1957; Rausch 1958) were largely outdated, especially due to some severe (a-)biotic changes that occurred during the decades following these publications. For me this was a good reason to start several studies on Middleton Island’s wildlife, focusing on the development of both vegetation and avifauna, in particular breeding birds. These studies started a year later and are keeping me pretty occupied up to the present day.
With this blog entry, the first of a series of three, I want to focus on the results of the 1956 biological reconnaissance of Middleton Island and share with you some of my thoughts on these and maybe present some preliminary results of my own studies in relation to these.
This first entry, however, is about a subject I know very little about and I can’t write much about either: the marine shells of Middleton Island. Now it already took me a considerable amount of time and effort some years ago finding a copy of Thomas’ 1957 vegetation study, I never managed to find a complete copy of Dallas Hanna’s and Hertlein’s work on the identified marine shells of Middleton Island. Until yesterday that is! The good news is that the whole edition of The Nautilus is now freely available online:

Dallas Hanna and Hertlein write about the collected material: “Twenty-one species are present in the lot and also one barnacle. To these may be added for reference purposes, two additional species cited by Dall (1921, pp. 32, 107) from Middleton Island. Thus the known marine mollusks from this island consist of 5 pelecypods, 14 gastropods, 3 chitons, 1 cephalopod and one barnacle. All, with one possible exception, are known to occur in waters of this general region at the present time. However, this one, Littorina arctica, may have been cited in Alaskan literature under a different name.” (Dallas Hanna and Hertlein 1959)

Now does this mean that the subject has been studied enough by now? Certainly not! Dallas Hanna and Hertlein already give two reasons why further study of the molluscan fauna could be very interesting:

“A geological investigation of the islands has been made by Don. J. Miller (1953), of the U. S. Geological Survey. During the course of his work he obtained 20 species of mollusks (identified by F. Stearns MacNeil) from Pleistocene sedimentary beds. Oddly enough, none of these species was found in the collection being considered here. It is practically certain that the lists of both fossil and recent species represent only a small portion of the total molluscan fauna of the island and adjacent waters.” (Dallas Hanna and Hertlein 1959)

Now I can come up with several more reasons to show some interest in the intertidal life around Middleton Island:

-  After the 1956 biological reconnaissance the 1964 Earthquake lifted up the whole island about 3.5 m on average, creating a new and more extensive intertidal zone around the island. This meant that the area that had initially been inspected by the 1956 field party currently makes up a permanent part of the island and does not contain live marine mollusks anymore. How did the new intertidal zone develop?

Intertidal area at the island's south end in 1960 (photo: Armand Biron)

Intertidal area in the upper east part of the island in 2005. No clear intertidal zone 
could be identified here before the 1964 Earthquake (photo: T. van Nus).

- The island remains under constant influence of seismic activity in the area, resulting in a small but continuing uplift or tilt (Prescott, W.H. and Lisowski, M. 1977; personal observations). It would be interesting to find out how over time this uplift affects the occurrence of mollusk species in the area

- Personal observations of the current intertidal zone indicate that this area can make up about half of the total size of the island itself (which is about 2 x 7.5 km). The new intertidal zone has become a majorly important foraging area for both breeding birds as well as a large number of spring and fall migrants, in particular shore birds. Very little is known what these birds find there and whether the availability of food is a limiting factor for them.

- Personal observations also suggest that intertidal life can be diverse but there are large annual changes occurring; in example the growth of kelp sp. varies a lot among years. Sea Otters (Enhydra lutris) established themselves for the first time in recorded history in the winter of 2008/2009 (van Nus, personal records). What is going on here?

Sea Urchins were very common during my first visits to Middleton in 2005 but were not 
seen often during later visits. At the same time growth of Kelp appeared to increase 
(photo: T. van Nus).

Now I never managed to find enough time to put effort into a study of the intertidal life around Middleton Island and I believe the challenge is still there, but it better needs to be done soon before another opportunity is lost..!


Miller, D. J. 1953. Late cenozoic marine glacial sediments and marine terraces of Middleton Island, Alaska Journal of Geology, 61:17-40.

Plafker, George, and Rubin, Meyer, 1978, Uplift history and earthquake recurrence as deduced from marine terraces on Middleton Island, Alaska, in Proceedings of Conference VI, Methodology for identifying seismic gaps and soon-to-break gaps: U.S. Geological Survey Open-File Report 78-943, p. 687-721.

Prescott, W.H. and Lisowski, M. 1977. Deformation at Middleton Island, Alaska, during the decade after the Alaska earthquake of 1964 Bulletin of the Seismological Society of America June 1977 67:579-586

Rausch R. 1958. The occurrence and distribution of birds on Middleton Island, Alaska. The Condor 60: 227-241.

Shepard Oldroyd, I. 1924 – 1927. The Marine Shells of the West Coast of North America.
Four Volumes. Stanford, California. Stanford University. 1520 pp. illus. ISBN: 9780804709873

Thomas, J. H. 1957. The vascular flora of Middleton Island, Alaska. Contrib. Dudley Herbarium, 5:39-56.

 Scattered boulders along the western shoreline (T. van Nus).

Thursday, July 12, 2012

Location and remains of the former fox farmer's station on Middleton Island

Between 1890 and the 1920’s Middleton Island was leased and inhabited by several individuals who operated a fox farm on the island. During this time a maximum of about 250 Arctic foxes Vulpes lagopus roamed freely about the island, living on whatever that was edible they could find (i.e. seabirds and their eggs), but were provided additional food if needed. Once a year a portion of their population got trapped by the farmers and their skins were sold on the fur market. More about this practice on Middleton has been written in several sources (i.e. Underwood 1913; Prichard Parker 1923; Bailey 1993; Crawford Isto 2012). Though it was obvious that their station over time had disappeared, as well as the foxes, for a long time the location of their former housing and whatever would be left of it remained a mystery.
During 2004 – 2006 the Federal Aviation Administration (FAA) funded a clean-up and restoration of an area in the north end of the island, containing a small and abandoned CAA (Civil Aeronautics Administration)/FAA settlement located on Chugach Alaska Corporation land. Most of the buildings and other constructions within this settlement were highly contaminated, many containing asbestos. Prior to this cleanup, in June 2004, an archaeological survey was conducted in the area of potential effect. The purpose of this visit was to determine if any archaeological material was in the area of potential effect (Grover 2004). 
Grover (2004) writes about the fox farmers: “Beginning in the 1890’s, Middleton Island was leased by fox farmers. A National Geographic article, A Northern Crusoe’s Island, describes one such enterprise that began in 1918. The unnamed couple that ran the farm found a horse on the island that had been left by previous fox farmers. The article described the farm and its buildings, but does not indicate where on the island they were located. The article states that there was a small, single story bungalow with a metal roof, a wood fence, at least one small outbuilding, rabbit houses, a root cellar, a tool shed, and a “Middleton Island Blue Fox Farm” sign (Prichard Parker 1923) (Fig 1 & 2). This is the only record found to date of the fox farming on the island.”
There has been, however a lot more written about the fox farming on Middleton Island (see Crawford Isto 2012 for a review). Grover (2004) did not find the location of the fox farmer’s station and as far as I know, no other source mentions this. I got the impression that among “insiders” it was thought that the site was “long gone”.

Figure 1: The fox farmer’s station on Middleton Island (Fred C. Schiller, National Geographic Society / Prichard Parker 1923).

Figure 2: Middleton Island’s “Blue Fox Farm sign” (Fred C. Schiller, National Geographic Society / Prichard Parker 1923).

I enjoyed reading Capps’ (1933) article “An Air Reconnaissance of Middleton Island”. This is the first geological survey made of the island. Capps writes: “In early May, 1932, the writer, while accompanying the Alaska Survey Expedition of the United States Navy, was given the opportunity to fly by plane from Seward to Middleton Island, in the hope that it would be possible to land there and to make some study of its geology. Upon arrival, however, it was found that although the sea appeared unusually smooth, a heavy surf was breaking entirely around the island, and it was unsafe to land. The best that could be done was to circle the island several times at various altitudes to obtain as thorough an inspection of it as possible. An excellent set of photographs was secured by the navy photographer, and the accompanying illustrations are here published by courtesy of the Hydro-graphic Office, Navy Department”. 
The article contains what probably are some of the earliest aerial photos of Middleton Island and also mentions the fox farmer’s station: “At present it is uninhabited, though for many years it was occupied as a fox ranch, and a few frame buildings, in bad repair, are still standing”.
During the 09/10 winter I was sent several historical aerial photos (Fig 3 & 4), some of which originated from the series taken during Capps’ flight in 1932, but these had not been included in this publication. Surprisingly, two of these photos showed what appeared to be a building located near the island’s north end. It occurred to me that, as there were no other inhabitants of the island at that time, this building must have been the fox farmer’s housing.

Figure 3: Previously unpublished(?) 1932 aerial photo. The arrow indicates the location of the suspected fox farmer’s station (source: unknown).

Figure 4: Another historical aerial photo of unknown origin, likely dating back to the 1930’s. The arrow indicates the location of the suspected fox farmer’s station (source: unknown).

After careful examination of the photos and comparison with more recent aerials I concluded that the particular location had not been affected by extensive soil disturbance that came with the construction of the CAA/FAA station in the north end during the 1940’s (Thomas 1957; Grover 2004). In fact, the location appeared to have been left virtually undisturbed during the last century. On several of the more recent (colour) aerials even some remains of the fox farmer’s station appeared to be visible, though I suspect that most of the material or whatever was left after Capps flew over the island had been raided by later visitors or CAA/FAA personnel (Fig 5 & 6).
The site was located just below the north-western bluff on a low slope that extended towards the beach and was adjacent to a small permanent drainage. The same drainage was later used by the CAA/FAA to feed their water supply for several decades in the mid 20th century. On the opposite side of this stream was located a large oil tank that was part of the former CAA/FAA station. It had been removed during the 2005 cleanup but remained visible on old photos, making it easy to find the location of the site. Somewhat remarkable was that the location was found right next to an archaeological survey route used by Grover in 2004, but it had apparently been missed (Grover 2004) (Fig 7).

Figure 5: A 1967 aerial photo showing the former CAA/FAA station at the north end. The red circle indicates the suspected location of the fox farmer’s station. Some debris may still be visible as a dark spot. It seems likely that the diagonal ditch visible to the southeast of the station had been dug out by the fox farmers to drain the fields containing their crops (source: unknown).

Figure 6: A 2002 aerial photo, showing the former CAA/FAA station at the north end. The red circle indicates the suspected location of the fox farmer’s station. Besides extensive soil disturbance resulting from the construction of the former CAA/FAA station, a lot more of Middleton’s history may be visible in the patterns visible in the vegetation on these high resolution aerials (source: unknown). 

Figure 7: Black & white copy of the archaeological survey route used by Grover in 2004. The red circle indicates the suspected location of the fox farmer’s station. Note the survey route running right next to the suspected location (red lines of the route are here shown in black and hard to see) (Grover 2004).

At arrival on Middleton in early April 2010 I was of course anxious to visit the location. It turned out to be easily approachable from the gravel road that crosses the drainage. I was surprised I had not set foot there before. The first notable thing was a large stand of Rugosa Rose Rosa rugosa, or a subspecies (Fig 8). This species has not been mentioned by Thomas (1957) and it was the first time I observed it on the island. In my opinion this didn’t mean that it only recently established itself on the island, but that the area rarely has had any visitors and had likely been overlooked during Thomas’ vegetation survey in 1956. I assume this plant was a clear remnant of the fox farmer’s garden, as their berries would have produced a valuable amount of vitamin C, quite necessary when being out there for a while (the fox farmers left the island usually only once a year by boat to sell their goods on the mainland and to refill their supplies). 

Figure 8: The large stand of Rugosa rose (Rosa rugosa) growing at the site (T. van Nus).

Straight through the site, however, ran an old rusty metal pipe, which had been in use to bring oil from the north end to a Cold War radar station located in the centre of the island. It had probably been placed there during its construction in the late 1950’s, meaning at that time visitors possibly have noticed remnants of the settlement.
Further investigation of the area revealed that there was a lot of debris of the station hidden under the vegetation. Various rusty metal objects, including a long (over 2 meters) saw blade,  pieces of coloured glass, a metal bowl and several other objects were collected and stored elsewhere on the island (Fig 9 & 10). Also visible were some remains of what appeared to be foundations of a building. I suspected this area held the single story bungalow. I found no remnants of the various sheds that had been there, but this particular area was heavily overgrown with Salmonberry Rubus spectabilis, making it difficult to find anything.

Figure 9: One of two rusty bowls that were found (T. van Nus).

Figure 10: Remains of a wood saw (T. van Nus).

After walking a few meters further down the slope some remnants of wooden poles became visible in the grassy vegetation. Obviously these were century old fence posts. I continued walking in a north-westerly direction, towards the shoreline on what I believe was once a trail that had been used often by the owners of the property to get to the nearby sandy beach. When approaching the sandy beach ridge my eyes were caught by remnants of two old wooden poles sticking out of the sand. These were a bit heavier than the fence posts found earlier and it immediately occurred to me that one hundred years ago these held up a “Middleton Island Blue Fox Farm” sign (Fig 11).

Figure 11: The author of this text in between the remains of the poles holding the “Middleton Island Blue Fox Farm” sign. In the back the low vegetated slope that once supported the fox farmer’s station (T. van Nus).

Shortly after the discovery I informed the Alaskan Office of History and Archaeology (OHA) about these findings by email. I never received a reply from them, which unfortunately, did not leave me with a very good impression of the archaeological community in this part of the world. For more than 200 years ‘soft gold’ brought many people to Alaska. Fur farming was Alaska’s third-largest industry in the 1920s (Crawford Isto 2012) but a disaster for wildlife (Bailey 1993). Due to the island’s location and recorded history, the finding of the remains of the fox farmer’s station on Middleton Islands deserves a bit more attention, in my opinion. Oh well, at least I got a good story out of it.

Acknowledgement: I thank Armand Biron for reviewing this blog entry and supplying me with some useful figures. Check out Armand’s impressive website dedicated to Middleton Island’s history, containing rather sensational historical photography:

Bailey, E.P. 1993. Introduction of foxes to Alaskan Islands – History, effects on Avifauna, and eradication. United States Department of the Interior, Fish and Wildlife Service. Resource publication 193. Washington DC.
Capps, S.R. 1933. An air reconnaissance of Middleton Ialand, Alaska: Jour. Geology, v. 41, p.

Crawford Isto, S. 2012. The Fur Farms of Alaska: Two Centuries of History and a Forgotten Stampede. University of Alaska Press. 230 p.

Grover, M.A. 2004. Archaeological Survey of Federal Aviation Administration Remediation, Middleton Island, Alaska. 16p.

Pritchard Parker, M. P. 1923. Northern Crusoe’s Island: life on a fox farm off the coast of Alaska. National Geographic 44: 313-326.

Thomas, J.H. 1957. The vascular flora of Middleton Island, Alaska Contributions from the Dudley Herbarium, 5:39-56.

Underwood, J.J. 1913. Alaska, an empire in the making. Dodd, Mead & Co., New York. 440 pp. Ills.

Sunday, July 8, 2012

Dietary specialization among the Glaucous-winged Gulls (Larus glaucescens) on Middleton Island

On Middleton Island a number of Glaucous-winged Gulls (Larus glaucescens) has specialized in taking alternative prey items. Some gulls out there are known to catch and eat young European feral Rabbits (Oryctolagus cuniculus) which were introduced to the island in 1954 (Roberts 1985; O'Farrell 1965). These two videos show how some Glaucous-winged Gulls try to catch a fledged Black-legged Kittiwake (Rissa tridactyla) chick and eat ripe Salmonberries (Rubus spectabilis) respectively. Further information can be found below the video on their individual Youtube pages.

It seems obvious that due to the island’s remote location the large Glaucous-winged Gull population has only limited access to terrestrial food items. Food shortage will therefore stimulate these birds more to explore new dietary items on the island. I am certain that there will be several more remarkable prey types utilized by them, and would very much appreciate it when visitors would inform me when they detect this.

O'Farrell, T.P. 1965. The Rabbits of Middleton Island, Alaska. Journal of Mammalogy, Vol. 46, No. 3, pp. 525-527
Roberts, B. 1985. Glaucous-winged Gulls prey on feral rabbits on Middleton Island, Alaska. Murrelet 66:24.

Saturday, July 7, 2012

A rough introduction to Middleton Island: 75 minutes of raw video footage

The following video material was shot during a visit in the summer of 2005. It contains raw footage, unedited, shot with a Sony miniDV camera, which only survived one season out on the island. Enjoy!