Habitat Restoration is "For the Birds" at Midway Atoll

One important part of our ecotourism programs to Midway Atoll is at least a 1/2 day spent giving back to Midway. Our visitors seem to relish in taking part in the "new" battle for Midway. Since Oceanic Society started bringing visitors to Midway way back in 1996, we have always tried to help the Fish and Wildlife Service in their efforts at habitat restoration. Over the years our volunteers have helped to "restore," I mean "pull weeds" at many different sites on Sand and Eastern Island. FWS has a master plan directed at how to try and combat the many invasive plant species that have found their way to Midway Atoll. On Sand Island alone over 240 non-native plant species exist. When you realize that if we could restore Midway to its original state (before people were living on the islands) there would only be about 37 native plants species that would/should be found there. That leaves about 200 species that are trying to out compete native species! While some may enjoy the various hibiscus and plumeria that are found on Sand Island it is the more insidious invasive species that are presenting the FWS with such a habitat restoration challenge. Species like lantana, Castor bean, and ironwood take major efforts to control. But the real thorn in the side of this endeavor is a plant called Golden crown-beard or Verbesina encelioides. "Verbesina" as it is called on the island is what most of our eco-volunteers spend their service afternoon battling. This desert adapted plant loves the sandy soil and disturbed ground conditions it finds at Midway. Add abundant rain during most of the year and this plant just takes off, growing in thick fields and sometimes getting to heights over 6-ft.!

One of the main reasons that invasive species are so bad on the island is that they tend to not offer the advantages to the resident seabird species nesting, that native plants do. For instance native grasses grow in bunches allowing for good air flow around nesting seabirds, helping to insure that they, and their chicks do not get overheated. Native ground covers work to both hold the sandy soil in place but at the same time not getting so dense as to inhibit burrowing seabirds from digging into the ground. Invasive species like Verbesina are bad by growing so thick they block wind flow (albatross nesting areas in Verbesina can be 10 degrees (F) hotter than the same type of nesting area with native grasses), and worse, the roots are so shallow that burrowing birds can burrow, but eventually many of the burrows will collapse, trapping adults or chicks inside. So much of the effort directed at invasive species control on Midway is to restore habitat to help enhance success of native seabirds that are nesting on Midway atoll. Everything from Laysan Albatross, to Red-footed Boobies, to Christmas Shearwaters benefit from the efforts of FWS and eco-volunteers to remove invasive flora and replant native species. These two pictures above show just how effective these efforts can be. They are both taken at the same location one year apart. The first picture shows our April '08 group out-planting bunch grass in an area that has a history of Verbesina control. The second picture taken this past April '09, and shows what that area and what the outplanted bunch grass (Eragrostis variabilis) looks like one year later. It is truly amazing how quickly these areas can be restored through regular weeding and outplantings. All of our service activities related to habitat restoration are under the guidance of FWS "weed combatant" extraordinaire Greg Schubert, who oversees the native plant propagation, habitat restoration, and weed control efforts at Midway Atoll. In January and February 2009 alone, Greg directed and participated in the out-planting of over 2000 native plants on Midway. His efforts to return to these outplanted areas on a regular basis, selectively controlling the invasives before they can reestablish, are an on-going management plan that is methodically and effectively restoring many acres of seabird habitat. Although I said these areas are quickly restored, that term is relative when you consider his 5 year commitment to this effort, and the fact that many more years, and volunteer efforts will be needed to see all of Midway's invasive species removed, or at least controlled.

Weeding also helps to open up space for nesting seabirds. This can be even more important when you are trying to opening up habitat area for endangered seabirds in efforts to have them recover historic breeding sites. Since 2001 Midway Atoll has utilized Short-tailed Albatross decoys to attempt to attract the Golden Goonies to once again nest on Midway's islands. On Eastern Island about 25 "fancy" decoys are placed out each year. Here is a picture from that first year when the plot was weeded to make sure that any passing Short-tailed Albatross would be sure to spot the brightly painted decoys. Short-tailed albatross recorded calls are also employed at the decoy site. This idea was conceived by Stephen Kress who has used the combination of brightly colored decoys and recordings successfully with puffins on rock islands in Maine. 8 years later the decoys and sound system seem to be working. Recently, an adult and sub-adult have been seen dancing at the decoy site. It is hoped that over the next few years Midway may see its first successful Short-tailed albatross nest in over 40 years! Thanks to the multi-year efforts of dedicated FWS employees and volunteers, hundreds of extra eco-volunteer hours, and original thinkers like Stephen Kress the new battle of Midway is slowly being won. Even though the Vebesina is still thick in many places, and other "bad" plant species like wild poinsettia and sandbur will create new problems, the current efforts of Greg and his crew are gaining ground. These small advances may seem to take forever for us, but for the seabirds that call these islands home, (and even those who are struggling to recover a home they once had) the ongoing habitat restoration efforts continue to help their populations recover from years of exploitation and decline at the hands of man. Short-tailed Albatross at decoy plot 2008

First Day on Midway Atoll - Oceanic Society Ecotourist Visitors

Well all 15 of us arrived on Midway Atoll at about 8:45 PM on the 13th of April. After a 4.5 hour charter flight from Honolulu we arrive at night. During the "albatross nesting season" planes are only allowed to land at night, when albatross are less likely to be flying and bird strikes are less probable. On arrival we are met by two Refuge "limo" golf carts and are whisked away to what will be our home for the next 8 days amid the whines of dancing albatross and the erratic flight paths of the thousands of swooping Bonin Petrels. Once settled in the lobby of Charlie Barracks we are given a brief orientation and allowed to head off to our rooms. Many people quickly return to the lobby eager to get outside and listen to the birds and take a long look at the amazing display of starts that being so far away from any light source allows.

In the morning we head off to breakfast at the "Clipper House" Midway's central hub and mess hall, named to honor the history of the Pam Am Clippers that used to stop here in the 1930's on their way to Asia. It was a wonderful morning and for many their first true glimpse (in the daylight) of what Midway has to offer.

New arrivals to Midway must take part in a FWS orientation as their first activity on Midway. Since we are all sharing the island with many critically endangered and threatened species this orientation is vital to the visitors ability to understand the responsibilities, and role they play while on Midway in the safe stewardship of these islands. Additionally the orientation serves to make everyone aware of the significance these atolls have played in Hawaiian cultural history as well as more recent US history. During the orientation, which is presented by FWS visitor coordinator, Tracy Ammerman, all are given a map of Sand Island. This map helps everyone to navigate on their own around the island, understanding which areas are open and have maintained trails, and what areas are closed due to conservation or safety concerns. The orientation and the lectures that will be given throughout the week help everyone to understand and appreciate why certain places on the island are left as wildlife only areas, and where viewing and access points for visitors have been established. After orientation the next order of business is for everyone to choose their own traditional Midway "horse" that will be used to get around the island over the next week. These "horses" or bikes that we have to choose from were all supplied through donations made to the Friends of Midway Atoll an organization formed to specifically support Midway Atoll National Wildlife Refuge.

Now that all the visitors have the needed knowledge to explore the island on their own and have a "horse" to navigate the paths full of albatross and chicks they are ready to enjoy the next 7 days on Midway. We are lucky to start off this week with amazing weather. One of the first places everyone wanted to go was the beach. We headed off to the cargo pier to see what we would find. On arrival we saw a Hawaiian monk seal on a nearby beach, about 16 green sea turtles sunning on an adjacent beach known oddly enough as "Turtle Beach" and then heard 7 Bristle-thighed Curlews as they flew overhead. As we looked down one side of the beach we noticed some washed up nets and marine debris that could pose a hazard to the wildlife we were seeing. The group decided to collect the various pieces of netting and line that were there. In about 10 minutes we had cleaned the beach of about 50-lbs of marine debris and taken our first action to participate in one of the missions of the Refuge, to provide a safe habitat for the wildlife that live there.














all images are © Wayne Sentman 2009

Plastic Debris and Albatross on Midway Atoll

Midway Atoll National Wildlife Refuge (MANWR) is encompassed in the newly designated, and second largest marine protected area in the world, The Papahanaumokuakea Marine National Monument (PMNM) (Figure 1). Midway Atoll lies 1200 miles northwest of Honolulu, Hawaii and is home to the worlds largest breeding colonies of two of the 3 North Pacific albatross species, the Laysan Albatross (LAAL), listed globally as vulnerable (IUCN 2008), and the Black-footed Albatross (BFAL), listed globally as endangered (IUCN 2008). The 2009 annual nest counts (every albatross nest on Midway’s 3 islands are counted) were just completed (2 January) and the preliminary data show 398,182 nesting pairs of LAAL and 23,955 nesting pairs of BFAL (USFWS, unpubl. data).

Figure 1 – Map Showing the Papahanaumokuakea Marine National Monument

Map reproduced with permission of NOAA monument office

Disturbingly these breeding grounds and the PMNM also are adjacent to two of the largest concentrations of floating marine debris in the world’s oceans. Plastic debris makes up the 90% of the floating marine debris found in the ocean (Weiss, 2006). One of those concentrations, the "Eastern Garbage Patch” is approximately twice the size of Texas (Silverman, 2007). Both Albatross species nesting on MANWR and throughout the rest of the atolls in the PMNM spend much of their time feeding in areas adjacent to or directly in this “Garbage Patch” (Fernandez et al. 2001 and Auman et al. 1997). It is primarily while feeding that albatross ingest a variety of plastic items (Figure 2).

Figure 2 - Diversity of Swallowed Plastic Items Recovered From Albatross Chicks

© 2009 Heidi Auman reproduced with permission

In doing so, they risk repeated exposure to an array of potentially toxic compounds (Jones et al. 1996, Ludwig et al. 1997, Mato et al. 2001, and Finkelstein et al. 2006). Further by regurgitating meals to their young, frequently loaded with this plastic, the true risks of this exposure may happen miles away from the point of contact, and some of these potential toxins may end up effecting the land-based albatross chicks more severely than the adults directly feeding in these areas.

Albatross chick carcass from Midway showing plastic present in gut at death.

© 2009 Wayne Sentman

Plastic debris has been identified as a growing problem in the Pacific Ocean (A.M.R.F., 2007). The currents or gyres that cause the pacific garbage patches to accumulate also are responsible for focusing some of that impact directly on LAAL and BFAL. This as a result of overlap between where these gyres concentrate marine debris and the areas of the north pacific in which the albatross are spending their time feeding (Naughton et al, 2007). Additionally while many species of seabirds are known to ingest plastic (Laist, 1997), both the LAAL and BFAL albatross chicks have been shown to regularly have relatively high, and increasing total amounts of plastic in their guts (Kenyon and Kridler, 1969, Auman et al. 1997, Naughton et al. 2007). This is also compounded (for chicks) by not being able to expel, through regurgitation, any items in their gut until about 3 to 4 months of age. Therefore plastic brought to the chicks through the parents many feedings tends to sit and accumulate in the chicks’ digestive tract for long periods of time.

© 2009 Wayne Sentman

This accumulated plastic has been shown to have detrimental effects to the success and survival of the albatross chicks (Sileo et al. 1990 and Fry et al. 1987). Additionally past research has shown high levels of organochlorine contaminants in albatross adults and chicks (Auman et al. 1997 and Finkelstein et al. 2007) and this likely has a relationship to ingested plastics.