Tagged: research

Local fisheries scientists working together to rehabilitate Brewer Pond

By Maja Cvetkovic, Carleton University’s Fish Ecology and Conservation Physiology Laboratory (FECPL)
Reprinted with permission from www.fecpl.ca

Last week post-doctoral researcher Dr. Jon Midwood led a group of volunteers from the FECPL lab and Ottawa community on a hunt for juvenile Muskellunge and Northern Pike in the Rideau River.

Ottawa can boast about its urban muskie population in the Rideau river, which winds through the city and provides unique habitat where both muskie and pike populations exist.

Volunteers seining the Rideau River for juvenile esocids.

Volunteers seining the Rideau River for juvenile esocids.

There is currently an active tracking project for adult muskie and pike in the Rideau River (click here to read about the Brewer Pond project), but the last time surveys were conducted for the juvenile fish was in 1999. With the International Muskellunge Symposium fast approaching (at Carleton, August 14th & 15th) and the Brewer Park Pond habitat creation project slated to break ground in mid-August, it seemed like a perfect time to get back out there to sample.

In association with Rideau Valley Conservation Authority (RCVA) and the Ottawa Chapter of Muskies Canada, FECPL members seined 12 sites on July 21st and 22nd. The main objectives were to 1) confirm muskies are still successfully spawning by finding young-of-year (YOY) and 2) determine if habitats near Brewer Pond are being used as nursery habitat by these YOY.

The surveys were a success. In the 12 sites that were seined, we found 14 juvenile muskies (averaging 10 cm in length) and 1 juvenile pike (130 cm in length). Esocids (either pike or muskie) were found in 8 of the 12 sites. It was especially gratifying since most of the volunteers seining ended up wading past the chest wader line and becoming thoroughly wet. Luckily it was a hot week so a thorough soaking was welcome despite the damp commute home. Well worth it!

Three young-of-year muskies caught in a seine haul in the Rideau River near Brewer Pond.

Three young-of-year muskies caught in a seine haul in the Rideau River near Brewer Pond.

Of course numerous other species were caught, including juvenile and adult Rock Bass, Pumpkinseed, Smallmouth Bass, Largemouth Bass, Walleye, Yellow Perch, as well as Golden Shiners, Blackchin Shiners, and some adult Northern Pike (a nice surprise to find in a seine net!). It was great to see the high level of recruitment of juvenile fish, especially in some of the embayments near Bronson St. Bridge that were created a decade ago for fish nursery habitat by the Ottawa Chapter of Muskies Canada in conjunction with RVCA/City of Ottawa.

So what does this tell us? First, it seems that muskies are successfully spawning in the Rideau River, and secondly, the habitats near Brewer Park Pond are being used as nursery habitat. Armed with this knowledge, it may be possible to link the tracking data from the spawning season with the locations where muskies were found to help narrow in on potential spawning locations.

Also, the presence of YOY muskies near Brewer Park Pond means that habitat remediation and creation work slated for late this summer will take place near an existing population. This population might be able to serve as a source for colonization of the newly created habitat (fingers crossed).

 

Carbon and caribou in Canada’s Low Arctic

By Claire Elliott, member of the OFNC

Claire Elliott

Claire Elliott

In the spring of 2013 I joined the research lab of Dr. Elyn Humphreys at Carleton University. Dr. Humphreys may be known to some OFNC members for her guided walks of Mer Bleue Bog. I was enticed to join the lab because of a unique opportunity to do field research in the Northwest Territories.

Our research program is focused on soil-plant-atmosphere interactions. Specifically, I use remote sensing technologies to investigate carbon exchange between the biosphere, the regions of the earth’s surface occupied by living organisms, and the atmosphere over large spatial scales. Remote sensing instruments collect data on the electromagnetic energy that has been reflected from earth. These sensors are typically mounted on satellites or aircraft, but similar handheld sensors have been designed for field use as well.

The Daring Lake Tundra Ecosystem Research Station.

The Daring Lake Tundra Ecosystem Research Station.


Currently I am living at the Daring Lake Tundra Ecosystem Research Station at Daring Lake NWT (64º 52’ N, 111º 35’ W). This region of the Canadian Low Arctic is called the Barrenlands by the local people, in reference to the lack of tall vegetation. I am here to assess the carbon source/sink status of this tundra ecosystem and to understand the biotic (e.g., vegetation, soil microbial communities) and abiotic (e.g., permafrost) controls on carbon exchange in the Canadian Low Arctic. Understanding the impacts of factors such as climate change will allow for better management of traditional lands and resources.

The vegetation in this image is red because photosynthesizing plants have high reflectance in the near-infrared (NIR) portion of the electromagnetic spectrum. The NIR band is loaded in the red channel of the image.

Photosynthesizing plants have high reflectance in the near-infrared (NIR) portion of the electromagnetic spectrum. The NIR band is loaded in the red channel of the image.

I spend my days collecting spectral information from a series of vegetation plots using a multispectral radiometer and specially adapted digital cameras. By measuring how vegetation reflects light from different parts of the electromagnetic spectrum, I am able to quantify the greenness or photosynthetic capacity (productivity) of the plants and see how this changes throughout the growing season. The productivity information I collect will be related to vegetation metrics (biomass, leaf area) and carbon exchange metrics collected for the same region. (See sample image at left.)

Prickly Saxifrage (Saxifraga tricuspidata).  This plant grows really well on the nutrient poor eskers.

Prickly Saxifrage (Saxifraga tricuspidata). This plant grows really well on the nutrient poor eskers.

For example, I will relate the seasonal trend in the productivity of my vegetation plots to a time series of the net ecosystem exchange of carbon to help quantify the biotic controls on carbon exchange. This will provide me with a better understanding of how the spatial structure of tundra vegetation communities relates to local carbon exchange processes. In the final step of my project, the relationships observed from the field data will be used to develop satellite measurements of vegetation productivity and carbon exchange metrics.

Aside from my research, I also enjoy a fantastic array of wildlife and plants in the area. Each morning I wake to the calls of the Yellow-billed Loons (Gavia adamsii), that breed on our lake. Throughout the day I see some of my other favourite tundra bird species, including the Harris’s sparrow (Zonotrichia querula), Red-necked Phalarope (Phalaropus lobatus), and Rough-legged Hawk (Buteo lagopus). There are plenty of mammals to watch for as well. Recently I watched a very bold red fox chase a wolverine up and over the esker behind our camp. On a slightly less dramatic note, I can see grizzly bears, arctic wolves, Bathurst caribou, and other northern species go about their daily routines during my time here on the tundra. This is a fantastic region of Canada to explore. I encourage everyone to visit the far north sometime in their life.

For more information on Arctic research and photos of Arctic wildlife follow Claire’s blog, “A Walk through the Woods”

All plant/wildlife photos taken by Claire Elliott.

Stories from Australia’s waves, caves, and animal graves

by Natalie Sopinka

On April 8, OFNC members met for the third time at the new meeting location at the Central Experimental Farm. Murray Citron recited his first-ever published poem (in Trail & Landscape!) which captured all elements of an Ottawa spring: wind, snow and sun. On that note, as spring temperatures rise, so do the number of OFNC events and excursions! All upcoming events are posted on the OFNC website.

Anouk Hoedeman updated attendees on the work of the new Ottawa Chapter of the Fatal Light Awareness Program (FLAP). Volunteers are urgently needed for pre-dawn patrols and for picking up and transporting injured birds to the Wild Bird Care Centre. If you are interested in getting involved, you can read more about FLAP Ottawa here or email flap@ofnc.ca.

The evening’s speaker was Dr. Kathy Conlan, a scientist at the Canadian Museum of Nature. Kathy, an expert in marine benthos and advocate of Antarctic research and conservation, shared in photographs and storytelling her recent travels to Australia with mineralogist Dr. Joel Grice. During a year-long sabbatical, Kathy and Joel embarked on four trips that took them to diverse habitats, from mangroves and rain forests to salt lakes and lava tubes.

Upwelling brings nutrient-rich water to the ocean surface promoting phyto- and zooplankton blooms. Photo: Google

Port Lincoln
Their first stop was along Australia’s southern coast – the Bonney and du Couedic submarine canyons, which are important to Australia’s fisheries because they channel seawater from a depth of a kilometre (or more) up to the surface. This “upwelling,” which happens when strong summer winds move surface water offshore, provides the phytoplankton in the nutrient-poor surface water with all the nutrients they need to grow and multiply. When phytoplankton “bloom,” zooplankton bloom too. Fish aggregate and feed on the zooplankton before being caught by fishers.

Kathy’s job on her sabbatical was to see whether these canyons also benefited the animals that live full time on the sea floor; her studies indicate that they do and that “upwelling is an important way of renewing ocean richness, rather like turning over the garden in the spring.” Kathy is quite fond of the animals that live on the sea floor, in particular species of the genus Jassa, which she has classified. She was surprised to find Jassa slatteryi in Port Lincoln as it is native to North America; the species may have crossed continents via ship ballast water. The gulfs in this area are teeming with sea grasses that support shrimp fisheries and are home to cuttlefish, leafy sea dragons, and bottlenose dolphins.

Flinders Range and Coober Pedy
Next Kathy and Joel traveled inland through Flinders Range encountering spectacular fauna including emus, eastern grey-kangaroos, rose-breasted cockatoos (or galah) and laughing kookaburra. The next stop was Coober Pedy, noted for their opal mines. Kathy found an opal potch, dull in comparison to jewelry or precious opal because the internal structure of the potch is less “organized” and does not diffract light the same way. Some inactive mines have been turned into underground campgrounds, one of which Kathy and Joel camped in.

Naracoorte and Tantanoola Caves
Heading southeast, Kathy and Joel were drawn to the World Heritage limestone Naracoorte Caves. Eroded by ground water the caverns were excellent traps for terrestrial creatures for 500,000 years. The perished megafauna were much larger than they are today and bones from over 100 species have been found to date. Nearby are the Tantanoola caves with stalactites that look like “falling caramel.”

Underground camping in Coober Pedy (left) and the Tantanoola Caves (right).

Underground camping in Coober Pedy (left) and the Tantanoola Caves (right). Photos: Kathy Conlan

Kathy scuba diving with a grouper on the Great Barrier Reef.

Kathy scuba diving with a grouper on the Great Barrier Reef. Photo: Oak Beach Productions, Port Douglas, Australia

Undara and the Great Barrier Reef
When Mount Undara erupted the lava radiating from the mountain flowed like molasses. The outer surface of the flows cooled forming a crust, and hotter liquids continued to flow underneath the crust, “like water in a hose.” When all the lava had flowed through, tunnels remained. Kathy and Joel walked throughout the lava tubes, which can flood during rainstorms.

The tour, and talk, ended with a diving session on the Great Barrier Reef. We saw cleaner shrimps, goby, lionfish, Moorish idol, humphead wrasse, leaf scorpionfish, seahorses and clown fish hiding among the magnificent fan, stony, zoanthid and soft corals. Sea turtles passed overhead and grouper said hello, before Kathy bid members good night.

 

Pukeko earn their badge

By Natalie Sopinka

Cody Dey with a pukeko.

Cody Dey with a pukeko.

Cody Dey, University of Ottawa alumnus and PhD student at McMaster University, is no stranger to the great outdoors. Cody’s passion for observing animals behave and immersing himself in the environments they inhabit has led him to many captivating places: snorkeling among Sand Lake’s smallmouth bass nests in Kearney, fly-fishing in the wondrous Alberta Rockies, and, most recently, studying the unique social hierarchies of New Zealand’s pukeko (Porphyrio porphyrio melanotus).

Pukeko are not your typical birds. Also referred to as purple swamphens, pukeko live in permanent groups with individuals competing against each other for mating opportunities, but also cooperating to raise chicks and defend territory against rival groups. Competition within a group results in the formation of dominance hierarchies. Hierarchies can be maintained by a range of different aggressive behaviours (e.g., pecking), but one has to ask: how do individuals know who’s the boss if all pukeko look the same?

Pukeko with red head shield. Photo by: Cody Dey.

Pukeko with red head shield. Photo by Cody Dey.

Cody’s PhD research, conducted at New Zealand’s Tawharanui Open Sanctuary, has provided answers to this question. Pukeko have bright red, fleshy shields on their head that they display when sparring with a competitor. Cody found that birds with larger shields displayed more aggressive behaviours and were more dominant within a social group. When the edges of the frontal shields were painted black to match feather colour and appear smaller, individuals were attacked and challenged more often. Having their social status threatened really went to their head; after only one week, manipulated individuals had reduced the size of their true shield.

Disentangling the dynamics of social signals and status remains a fascinating topic in behavioural ecology as signals of social status are found throughout the animal kingdom – from black facial spots on wasps and colour changing stripes on fish to the bellows of deer and thundering roar of a human’s sports car, although the latter has yet to be supported scientifically.

For more information on pukeko check out Cody’s interview on CBC’s Quirks and Quarks and his video, Badge of Status.

View from Tawharanui Open Sanctuary, New Zealand. Photo by Cody Dey.

View from Tawharanui Open Sanctuary, New Zealand. Photo by Cody Dey.