New Zealand’s mega-fauna come to Newport, Oregon.

By Olivia Hamilton, PhD Candidate, University of Auckland, New Zealand.

The week leading up to my departure from New Zealand was an emotional rollercoaster. Excited, nervous, eager, reluctant… I did not feel like the fearless adventurer that I thought I was. D-day arrived and I said my final goodbyes to my boyfriend and mother at the departure gate. Off I went on my three-month research stint at the Hatfield Marine Science Center.

Some thirty hours later I touched down in Portland. I collected my bags and headed towards the public transport area at the airport. A young man greeted me, “Would you like to catch a taxi or a shuttle, ma’am?” “A taxi please! I have no idea where I am”, I responded. He nodded and smiled. I could see the confusion all over his face… My thick kiwi accent was going to make for some challenging conversations.

After a few days in Portland acclimatizing to the different way of life in Oregon, it was time to push on to Newport. I hit a stroke of luck and was able take the scenic route with one of the girls in the GEMM lab, Rachael Orben. With only one wrong turn we made it to the Oregon coast. I was instantly hit with a sense of familiarity. The rugged coastline and temperate coastal forest resembled that of the west coast of New Zealand. However, America was not shy in reminding me of where I was with its big cars, drive-through everything, and RVs larger than some small kiwi houses.

The Oregon Coast. Photo by Olivia Hamilton.
The Oregon Coast. Photo by Olivia Hamilton.

We arrived at Hatfield Marine Science Center: the place I was to call home for the next quarter of a year.

So, what am I doing here?

In short, I have come to do computer work on the other side of the world.

Dr. Leigh Torres is on my PhD committee and I am lucky enough to have been given the opportunity to come to Newport and analyze my data under her guidance.

My PhD has a broad interest in the spatial ecology of mega-fauna in the Hauraki Gulf, New Zealand. For my study, megafauna includes whales, dolphins, sharks, rays, and seabirds. The Hauraki Gulf is adjacent to Auckland, New Zealand’s most populated city and home to one of our largest commercial ports. The Hauraki Gulf is a highly productive area, providing an ideal habitat for a number of fish species, thus supporting a number of top marine predators. As with many coastal areas, anthropogenic activities have degraded the health of the Gulf’s ecosystem. Commercial and recreational fishing, run-off from surrounding urban and rural land, boat traffic, pollution, dredging, and aquaculture are some of the main activities that threaten the Gulf and the species that inhabit it. For instance, the Nationally Endangered Bryde’s whale is a year-round resident in the Hauraki Gulf and these whales spend much of their time close to the surface, making them highly vulnerable to injury or death from ship-strikes. In spite of these threats, the Gulf supports a number of top marine predators.  Therefore it is important that we uncover how these top predators are using the Gulf, in both space and time, to identify ecologically important parts of their habitat. Moreover, this study presents a unique opportunity to look at the relationships between top marine predators and their prey inhabiting a common area.

The Hauraki Gulf, New Zealand. The purple lines represent the track lines that aerial surveys were conducted along.

 

Common dolphins in the Hauraki Gulf. Photo by Olivia Hamilton
Common dolphins in the Hauraki Gulf. Photo by Olivia Hamilton

 

A Bryde’s whale, common dolphins, and some opportunistic seabirds foraging in the Hauraki Gulf. Photo by Isabella Tortora Brayda di Belvedere.
A Bryde’s whale, common dolphins, and some opportunistic seabirds foraging in the Hauraki Gulf. Photo by Isabella Tortora Brayda di Belvedere.

 

Australisian Gannets and shearwaters foraging on a bait ball in the Hauraki Gulf. Photo by Olivia Hamilton.
Australisian Gannets and shearwaters foraging on a bait ball in the Hauraki Gulf. Photo by Olivia Hamilton.

To collect the data needed to understand the spatial ecology of these megafauna, we conducted 22 aerial surveys over a year-long period along pre-determined track lines within the Hauraki Gulf. On each flight we had four observers that collected sightings data for cetaceans, sharks, predatory fish, prey balls, plankton, and other rare species such as manta ray. An experienced seabird observer joined us approximately once a month to identify seabirds. We collected environmental data for each sighting including Beaufort Sea State, glare, and water color.

The summary of our sightings show that common dolphins were indeed common, being the most frequent species we observed. The most frequently encountered sharks were bronze whalers, smooth hammerhead sharks, and blue sharks. Sightings of Bryde’s whales were lower than we had hoped, most likely an artifact of our survey design relative to their distribution patterns. In addition, we counted a cumulative total of 11,172 individual seabirds representing 16 species.

Summary of sightings of megafauna in the Hauraki Gulf.

Summary of sightings of megafauna in the Hauraki Gulf.My goal while here at OSU is to develop habitat models for the megafauna species to compare the drivers of their distribution patterns. But, at the moment I am in the less glamorous, but highly important, data processing and decision-making stage. I am grappling with questions like: What environmental variables affected our ability to detect which species on surveys? How do we account for this? Can we clump species that are functionally similar to increase our sample size? These questions are important to address in order to produce reliable results that reflect the megafauna species true distribution patterns.

Once these questions are addressed, we can get on to the fun stuff – the habitat modeling and interpretation of the results. I will hopefully be able to start addressing these questions soon: What environmental and biological variables are important predictors of habitat use for different taxa? Are there interactions (attraction or repulsion) between these top predators? What is driving these patterns? Predator avoidance? Competition? So many questions to ask! I am looking forward to answering these questions and reporting back.

North to the land of liquid sunshine and red-legged kittiwakes – Linking individual foraging behaviour and physiology to survival and reproductive output

My name is Rachael Orben and I am a postdoctoral scholar affiliated with both the Seabird Oceanography Lab and the GEMM Lab here at Hatfield Marine Science Center. I am writing this from Anchorage, Alaska where Abram (a Master’s student at San Jose State University) and I are just finishing gear gathering and shopping before flying on to St George Island to spend the end of May and June observing, tracking, and sampling red-legged kittiwakes.

This video is taken looking down to the beach from the top of High Bluffs, St George Island.  Turn up the volume!

Just a little bit of background

Red-legged kittiwakes are endemic to the Bering Sea and most of their population nests on the cliffs on St George Island. St George is one of the Pribilof Islands located in the southeastern Bering Sea and is home to over a million nesting seabirds including auklets, cormorants, kittiwakes, murres, and puffins.  The Pribilofs are also known for the large rookeries of Northern Fur Seals (http://www.afsc.noaa.gov/nmml/education/pinnipeds/northfs.php).  St. George has a small Aleut community (http://www.apiai.org/tribes/st-george/) so we will be living in town and commuting by ATV and foot to the bird cliffs.

 

Click on the link below – Can you spot the red-legged kittiwake?

SeabirdsofPribilofs

Photo credits: Caitlin Kroeger

 

We would like to know how individual foraging behaviour and physiology influence reproductive success and then how these might carry over to wintering behaviour.

 

Tracking: We will be using GPS dataloggers (10g) and geolocation/wet-dry dataloggers (1g) to track movements and foraging behaviour of red-legged kittiwakes during incubation and overwinter.

GPS
GPS Logger from Rachel’s Kittiwake study

 

 

Physiology: When we catch birds we will take physiological samples to measure individual stress levels, mercury loads, and body condition that we can link to foraging behaviour.

 

Observations: We will observe the birds that we track so that we know when eggs are laid, chicks hatch and fledge so that foraging and physiology can be connected to these measures of breeding success.  And next year we will return and resight these birds to measure survival.

 

This study is funded by the North Pacific Research Board (http://www.nprb.org/) with additional support from OceanClassrooms (http://oceanclassrooms.com/) for pre-breeding tracking.  I also have been writing short blogs about project with the Seabird Youth Network aimed for middle schoolers that you can check out here:  (http://seabirdyouth.org/category/kittiwake-behavior/)

 

Internet access will be intermittent on St George, but I hope to periodically post updates via Twitter @RachaelOrben (#OCGrants), Instagram @raorben, and the Seabird Youth Network Blog.

CliffsofStGeorge
Cliffs of St. George

 

Seabird Research on the Western Antarctic Peninsula

I’d venture to say that I’m not the first field biologist to stare into the distance past my computer for a long while before deciding that trying to describe the smell of a seabird colony in a blog was futile.

My name is Erin Pickett and I am a graduate student at OSU’s Marine Mammal Institute. I am affiliated with the Biotelemetry and Behavioral Ecology Laboratory, a sister-lab of GEMM, and am here to share my recent experience conducting field research in Antarctica.

I’ve recently returned from a field season at Palmer station on Anvers Island, along the Western Antarctic Peninsula. Throughout the month of January I was collecting data for my masters’ project, while partaking in an on-going study conducted by the Palmer Long Term Ecological Research (LTER) program. I was fortunate enough to join the seabird research team at Palmer, a group that has been monitoring the area’s breeding seabirds for over two decades. January is the team’s busiest Antarctic summer month as the seabirds are in the midst of their annual breeding season. Our primary focus was studying the foraging ecology and demography of Adelie penguins; however, we also monitored Chinstrap and Gentoo penguins, southern giant-petrels, brown and south polar skuas, and blue-eyed shags. Before I delve into a description of this research, I’ll tell you a bit more about what it’s like to work in Antarctica.

It became quickly apparent to me that working with a team of experienced field biologists who have spent a collective thirty or so seasons in Antarctica meant that I would be the only one distracted by the scenery. This situation was exacerbated by the fact that I had never witnessed snow falling before I had arrived in Antarctica. I tried to play it cool, but inevitably rolled down every snow-covered hill I came across, and I couldn’t help but stop and stare into the sky every time it snowed.

There might have been some misunderstanding when in an email to a friend I referred to the weather as balmy. By Antarctic standards this was true, the average daily temperature hovered around 35°F. By my Hawaii-born standards, it was only balmy once I donned three or four layers, slipped toe warmers in my boots, and sipped on hot coffee while I hiked up a hill. Still, I considered myself lucky to have escaped my first Oregon winter by travelling south.

At Palmer I quickly learned that birders don’t come in for lunch. I adjusted my rations accordingly, although I have to admit that my “emergency food” in my “emergency boat bag” got eaten despite the fact that no real (non-hunger related) emergencies occurred. Every day after packing lunch and suiting up, we would load a small zodiac with our gear and set off to work on the numerous islands surrounding the station where seabirds were nesting.

One of the main objectives of the Palmer LTER program is to research the effects of climate variability and change on the marine ecosystem surrounding Palmer station. As an apex predator, the Adelie penguin plays a focal role in this project by providing insight into ecosystem-wide changes in the marine environment and the surrounding coastal habitat. Over the last four decades, Adelie penguins on the Western Antarctic Peninsula have experienced a decline of over 85% of their population. During this same time period Gentoo and Chinstrap penguins, who were previously unknown in this area, established founder colonies and they have been increasing in number ever since.

These recent population trends have been alarming and have driven Palmer LTER research objectives aimed at understand the mechanisms behind these changes. The proximal cause behind these demographic shifts is a warming-induced loss of sea ice along the peninsula. Over the last 50 years, the average mid-winter temperature in this region has risen by 6°C (five times higher than rise of the average global temperature). By decreasing the extent, duration and concentration of winter sea-ice, this warming has altered marine primary productivity and transformed coastal habitat along the peninsula.

These transformations have caused the climate along the WAP to more closely resemble the warmer and moister sub-Antarctic, rather than the traditionally cold and arid Antarctic it once was. This has resulted in a southward expansion of the ranges of sub-polar, ice-avoiding species (e.g. the Gentoo penguin) and a contraction of the ranges of ice-obligate species (e.g. the Adelie penguin). The strong influence of sea ice on the ranges of these two species makes it difficult to determine whether sea ice driven marine variability has also influenced these trends. The life history of Antarctic krill, a primary prey item of both Adelie and Gentoo penguins, is intricately tied to the seasonality of sea ice. In regions north of Palmer, decreasing sea ice has resulted in declining krill stocks. In the future, trends at Palmer are predicted to mirror those seen in the northern WAP.

For my master’s research, I am working with the seabird biologists at Palmer station to gain a better understanding of how prey variability affects the foraging strategies of Gentoo and Adelie penguins in this area. Specifically, I will be investigating how the foraging behaviors of Adelie and Gentoo penguins change in relation to inter-annual krill recruitment variability. I will be utilizing a long time series of data collected at Palmer by outfitting Adelie and Gentoo penguins with satellite transmitters and time depth recorders. This data will allow me to describe the foraging behavior and effort expended by these penguins on the daily foraging trips they make to feed their chicks. Determining how each of these species responds to prey variability will help us better understand the current community structure of penguins at Palmer. This is important because it will leave us better informed to predict the effects of future ecosystem shifts on the reproductive success and geographic distributions of these two species.

I’m looking forward to sharing more of this research as time goes on. Until then, enjoy the photos!