Heading out of the volunteer house around sunrise, I bike towards the USFWS Midway Atoll NWR Office. The weather looks promising today, with a clear sky overhead, already filled full with our feathered friends, the albatross. Hundreds, perhaps even thousands of them are taking to the sky, aided by the warm breeze this morning. Up and up into the air they glide, crisscrossing each other. Meanwhile, back on the ground, thousands more albatross sit quietly, some with eyelids half closed, as they patiently incubate their precious, single egg. I stop by Parade Field and get off of my bike, savoring the moment and one of the best views of the hundreds of thousands of nesting albatross (both Laysan and Black-footed) at Midway. A few minutes later, I’m in the office, greeted warmly by the USFWS staff. We exchange weekend stories and the latest updates about the upcoming ukulele concert (believe it or not, Midway Atoll boasts quite a rockin’ ukulele band). Then we focus on today’s agenda. No day is quite the same out here at Midway Atoll NWR.
As wildlife biology volunteers, we help with a variety of hands-on habitat and wildlife related work around Midway Atoll NWR. Depending on the priority of various projects and the status of wildlife around the atoll (i.e. incubating albatross, albatross with chicks, or just albatross chicks), our agenda changes accordingly. We arrived at Midway during the start of the breeding season for Laysan and Black-footed Albatross, so much of our work currently focuses on collecting demographic data on these species. However, a “typical” day at work is more than simply banding birds and data entry. Our work switches from “seep” checks (checking for signs of botulism among Laysan Ducks [Anas laysanensis]), to reproductive success monitoring of Laysan (Phoebastria immutabilis) and Black-footed Albatross (Phoebastria nigripes), to cloning native Bunch Grass (Eragrostis variabilis) for outplantings around Sand Island to enhance habitat quality for the full diversity of nesting seabird species here. And, of course, careful data entry. Singled out, these individual tasks might seem a bit random but in reality, many (if not all) of these tasks are closely connected with one another.
To elaborate, I’ll start with the Laysan Duck, one of the world’s most endangered ducks. Once common in many of the Hawaiian Islands, this small, dabbling duck came very close to extinction, mainly due to the introduction of non-native mammalian species and later the introduction of European rabbits (Oryctolagus cuniculus) on Laysan Island, the island with the last remaining Laysan Duck population. As part of conservation efforts, several Laysan Ducks were translocated to Midway Atoll NWR in 2004-2005 to restore a second population of ducks in their historical native habitat. Ten years later, the Laysan Ducks are thriving out at Midway Atoll NWR although they face ongoing threats of avian botulism, a paralytic, often fatal disease caused by the ingestion of a toxin produced by the bacterium, Clostridium botulinum. From a global perspective, avian botulism outbreaks kill thousands to hundreds of thousands of waterfowl, shorebirds, and other water-loving birds each year. Unfortunately, avian botulism has become increasingly prevalent all over the world, mainly due to the effects of human activities upon wetlands and other wet habitats, such as wetland flooding and draining, increased pesticide use, and dumping of raw sewage. While these particular sources of botulism are not present at Midway, other environmental conditions for botulism to flourish do exist (such as warm ambient temperatures, pH, salinity, etc.). It's not the anaerobic bacterium C. botulinum that kills waterfowl though; instead, it is the toxin produced by C. botulinum that kills the species in question. The production of the toxin takes place in decaying waterfowl carcasses by C. botulinum; flies then deposit eggs on carcasses which are fed upon by resulting maggots. The maggots concentrate the toxin (biological magnification) and these toxic maggots are ingested in turn by other waterfowl, which results in more bird deaths, more carcasses in which toxin production can take place, and more toxic maggots for other birds to feed on. The cycle accelerates and major die-offs occur. C. botulinum can materialize and multiply quickly, so our bi-weekly “seep” (i.e. pond) checks are essential in detecting any sick ducks and treating them quickly and effectively so as to keep the Laysan Duck population healthy and stable and reduce the risk of avian botulism outbreaks and consequent die-offs.
In addition to Laysan Ducks, we also focus on other water-loving birds, specifically albatross. Even though these “gooney” birds seem to inhabit every nook and cranny on Midway Atoll NWR, little is known about the lives of these birds beyond the breeding colony. What we do know is that they are captains of the sea and air, flying thousands of miles each year in search of food. In fact, these birds spend the majority of their lives, nearly 90%, up in the air. But, out at sea albatross face many threats, most notably commercial fishing practices such as pelagic longlines. To estimate Laysan and Black-footed Albatross species' populations and long-term viability as well as the effects of various human activities and environmental factors on these species, we collect information on reproductive success and survival. At this time, most of the albatross across Midway Atoll have recently laid eggs so we have just begun with our reproductive success monitoring. Throughout Sand Island at Midway Atoll NWR, we monitor reproductive success at specific plots; within in each plot, we identify all albatross nests and keep track of each nest from freshly-laid egg to fledged chick. Based on this data, we can get a rough idea of how many chicks survive and in turn what the long-term success “rate” is. Survival monitoring is quite similar, in that we only focus on the adults that return to specific survival plots each year. Albatross are quite philopatric (meaning that they come back to nest at the same spot, usually within a few meters, each year) so there’s a good chance we’ll come across long-time residents within a given plot. Not only does this data give us a sense of the adult survival (or more specifically, survival of returning adults) but it also gives insight into the frequency at which albatross breed (that is, if they breed every year or if they occasionally take a year off to molt or undertake any other energetically intense activities). While the percent of chicks that survive the initial treacherous trek out to sea or the survival rate from chick to breeding age are unknown, these basic data on reproductive success and adult survival give us valuable information and insight into long-term demographic trends.
Even though there are some threats that we can’t readily address from Midway (such as pelagic longlines and albatross bycatch mortality) we can focus on one thing: habitat. Prior to the twentieth century, at least 37 native plant species were thought to have occurred at Midway. Currently, only 20 native species (6 endemic, 1 species of concern) occur on Midway Atoll and at least 15 (9 endemic) have been extirpated and 2 (both endemic) are thought to be extinct. The total number of species (native and non-native) ever recorded from Midway Atoll is 354 with a total of 264 being present during the last major botanical survey between April and June 1999. Needless to state, Midway Atoll is “a highly disturbed system that hosts invasive plant species, toxic materials, and human development remnants that, taken together, have created significant adverse impact on indigenous species and their habitat.” Some of the most problematic species are those that colonize aggressively, grow quickly (especially vertically) and create monotypic stands, most notably Golden Beardtongue (Verbesina encelioides) and Ironwood (Casuarina equisetifolia). Seabirds, specifically Laysan and Black-footed Albatross, are often ground-nesters; plants that drastically alter the vertical structure of breeding colonies can have detrimental effects on reproductive success. For example, before Golden Beardtongue was aggressively treated with herbicides, it grew so dense and so tall in certain patches that albatross chicks were unable able to fledge and died in the thick, literally, of Golden Beardtongue stands. To create and maintain quality habitat for the 2-3 million seabirds that breed here each year, vegetation-related work is a significant part of volunteer work. Often times, we help with hand-pulling certain invasive species (so long as the disturbance does not affect the seed bank in the soil substrate or spur more growth), spraying herbicides (on select Ironwood trees encroaching on beaches or spot-treating for specific invasive species), transplanting cuttings of native species like Sea Purslane (Sesuvium portulacastrum), or working in the greenhouse on cloning dune-stabilizing species such as Bunch Grass (Eragrostis variabilis).
While it would take pages more (probably multiple books, knowing me) to explain everything that I've learned since arriving at Midway, one of the most important lessons that I've picked up is that whatever field you go into, whether it be microbial biology or avian physiology, ecology is at the heart of these professional studies. That is to say, understanding a system in its entirety is key. While we may care strongly about the long-term stability of the various seabirds that breed on Midway Atoll NWR each year, we also have to know about what abiotic and biotic factors that are important, perhaps even pivotal, in the survival of these species and what we can do to ensure that these resources remain available to these species into the future.
Not only are we, volunteers, fortunate enough to work in such a unique environment such as Midway Atoll NWR but we also have the opportunity to engage in real and meaningful conservation and resource management work on the frontline. Jumping into seeps and digging out weeds, we love it all.
After work one day, I go down to the beach and stroll around, looking out at the afternoon sunlight reflecting off of the choppy waves. Beyond the horizon, I know that there are innumerable issues that await the albatross. Pelagic longlines under the waves, plastic bottlecaps floating along. In the simplest sense, it’s overwhelming. At the same time though, oddly enough, being on Midway is an incredibly inspiring experience. With all the work that I do each day out here, I feel like at least I’m doing something, rather than twiddling my thumbs and worrying about the unreachable issues that I can’t address. I sit down and as I do so, a Laysan Albatross comes waddling out from behind a Naupaka shrub. I see that is has an aluminum band on its left leg and I squint, trying to read a few of the identification numbers on the band. It is heavily worn and the numbers have faded away. We stop and look at each other for a few moments. Albatross are incredibly long-lived species and this particular bird could be the same age, maybe even older than me. I wonder what it has seen out at sea but then also marvel at the triumph that this species is, to be alive and well despite the woes in the world.
***Huge thanks to fellow wildlife biology volunteer, Greg Joder, for sharing pictures of Midway Atoll NWR's volunteers at work in the field! Be sure to check out Greg's amazing blog and photography here!
Wieteke Holthuijzen: budding environmental scientist, passionate birder.