KOLOA DUCK RESEARCH IN HANALEI – AGAIN
Birds have always fascinated man with their ability to do something man cannot: FLY. It is for this reason we still know so very little about them. Being the primary wildlife of the islands, I’ve developed a keen interest in these feathered friends. Since I live in Princeville between wildlife refuges at Kilauea and Hanalei I am very lucky to be around so many critters that are considered rare, the Hawaiian Duck, or Koloa being one of them.
Koloas are shy and flush from their wetland home with the slightest human noise – walking within thirty feet of them causes them to take off. I met Christopher Malachowski last year on a wetland tour, a masters student from Oregon State University. H
Later I spent one day with him while he took data including blood samples for DNA from a few he had trapped.Kauai has the purest remaining strain of the little plain brown Koloa ducks. They are on the borderline of extinction and the few remaining on other islands have nearly all become diluted into hybrids with Mallard ducks brought to the islands for hunting.
Later I spent one day with him while he took data including blood samples for DNA from a few he had trapped.
Chris with a spotter - Hanalei 2011
Last month I jumped at the invite to participate in his current doctoral project. This time he had 65 transmitters and a veterinarian on island to surgically implant them – these will help him gain data on their movements, the trickiest part of human/bird studies.
Refuge biologist, Kim Uyehara supervises the process taking place in Hanalei Refuge. Chris continually improves his system and volunteers are recruited to record data as he measures and weighs. Most of the volunteers are interns from Americorps with very few of us from outside the circle.
At sunrise we go to traps that were baited the prior evening. As many as five traps are set throughout the wetlands. The taro farmers start early so we try to stay ahead of them; the less commotion for the birds, the more comfortable they are.
The first trap to be checked is in the grassy pond at right of dyke
Chris and interns Marie and Kristina returning with duck crates and supports
At each trap any ducks are collected and placed in crates. Occasionally other birds are caught; they are released on the spot. For the Koloas, males are placed in one crate and females in the other. The large crates are returned to the dyke where the tail-gate station is set up, with a canopy if raining or if very hot out. Sheets are placed over the crates to reduce stimulus, an effort to keep the birds calm. One by one each birds stats are taken and recorded: weight, age determination, and overall health; each bird is banded. Females are assessed first in order to quickly release any egg bearing or brooding females.
Coloration at wing (plumage) helps determine if a bird is a juvenile or an adult
The shortened stat sheet
Chris & Jimmy with w62
The USGS number on the aluminum band goes into an international data base
The USGS number on the aluminum band goes into an international data base
for all banded birds, not just Koloa Ducks
Key to the program is limiting stress for the individual birds. Chris can do the stats for most birds in eight minutes. If they are not candidates for transmitters, their data goes on file and they are released. Birds receiving transmitters are caught, assessed, have the surgical implant and are released the same day!
Healthy, adult females without brood patches or eggs are candidates for transmitter implant and are placed in carriers after stats are taken and banding completed. The carriers are set aside and covered so the birds remain calm. Males are then assessed and released or set aside for transmitter duty.
Each empty carrier has a clean towel inside and
there are a stack of clean towels to place over the carrier once the bird is inside
Birds caught that already have bands are cross-checked against a list of leg band numbers for their history. If not transmitter candidates they are released. Juvenile birds are released after stats and banding.
Kim holds this one 'till he calms down then sets him on the water
Off he goes!
Kim and I drove the new recruits to the lab where the veterinarian would do another assessment for health and take DNA tissue before implanting the VHF transmitter in a bird's abdomen. We placed the incoming carriers on the porch to the right of the door with their seclusion towels in place.
Birds that had become alert after their surgery were in covered carriers to the left of the door. Kim went on to a meeting and I drove the birds to the vicinity where they were captured for release (in the event they were from a pair). Overall time from capture to re-release was just under two hours.
Birds that had become alert after their surgery were in covered carriers to the left of the door. Kim went on to a meeting and I drove the birds to the vicinity where they were captured for release (in the event they were from a pair). Overall time from capture to re-release was just under two hours.
With two to release, I just opened the carrier doors and uncovered them as I stepped back
They were gone before I could say "safe journey"
December 16, 2012
I volunteered two days in November before my trip to Colorado
Kim on left, Chris on right, AmeriCorps intern Jimmy at center
The large orange crates are lined with mesh
so there are no sharp edges for the birds to scrape.
Chris has placed large metal crates in the water for the orange ones to rest on
Males in one, females in the other
I'm calming wMR before release
Of the two males, one was released and the other received a transmitter.
The female received a white band numbered MU.
At just a few grams, the transmitter weighs less than a portion of the daily food intake would weigh.
w MU getting the transmitter inserted
She will be out from under anaesthesia in minutes
We don’t have an accurate count of the remaining Koloa Ducks. We don’t know how far they fly and how many nest up river. We don’t know for sure if they travel inter-island. Collecting the data from the transmitters will not give all of these answers, but it will give some answers that may help dedicated conservationists determine how to protect the little endemics that took thousands of years to evolve before becoming game to humans.
In 1900 Koloa ducks were still on all the large main islands. As of the 1920s, the bag limit was 25 per day! Hunting was prohibited in 1939 but much of their marshland habitat has now been commercially developed. See earlier post regarding Avian Botulism that may be their biggest threat today. Cross your fingers it is not too late.
This is what HOPE looks like
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