Institute for Environmental Monitoring and Research

< River Valley

RIVER VALLEY ECOSYSTEMS PROJECT:
An Investigation of Two River Valleys
in Quebec-Labrador

BACKGROUND
River valleys within the Military Training Area (MTA) of Quebec-Labrador are frequently subjected to low-level jet overflights, likely because they provide a natural corridor suitable as training routes and they enable pilots to train in radar masking topography. The unique landscape and topographical features of river valleys, such as steep sided hills and partially vegetated plateaus, that attract military overflights, also support a unique variety of plant and animal life.

Little Mecatina River

St. Augustin River

Many plant and animal populations are restricted to river valleys due to the physical constraints of the landscape, such that the dispersal of populations is often though river valley corridors. Given the relative amount of military low-level flight training occurring in river valleys, coupled with their potential biological importance, the Institute is developing a research program to investigate the impact of overflights on ecological components of river valleys

THE RIVER VALLEY ECOSYSTEMS PROJECT
In 1999 and 2000, the Institute held two River Valley Ecosystems Workshops, attended by university and government based scientists along with aboriginal advisors and Institute staff to assess the viability of a study on river valley resources. The workshops set the framework for a long-term field study of river valley ecosystem components and the impact of low-level military training activities on these components. Working hypotheses, an overall experimental design, key wildlife taxa to study, and potential river valleys to conduct the research were identified.

Field staff Kathy Hogan and Coreen Michelin on hilltop overlooking the Little Mecatina River

Cabin used by local Innu at the St. Augustin River

In the fall of 2000, the Institute, in conjunction with Jacques Whitford Environmental Limited, conducted a field reconnaissance of the two river valleys considered for investigation. Sections of the rivers appropriate for field investigation were identified and the general habitat composition of the sections were mapped.

Float plane landing on St. Augustin River

Traditional Labrador tent used in field camps

In the summer of 2001, the Institute began a pilot study examining the community composition, abundance, and habitat associations of forest songbirds and small mammals within the Little Mecatina and the St. Augustin river valleys. The information collected from the pilot study will provide the basis for future research of river valleys located in the Military Training Area (MTA). Through potential research initiatives, there exists opportunities for university lead studies of cause and effect relationships between abundance, diversity, behavior, and/or reproductive success of selected wildlife species and low-level over-flights in the river valleys.

RESEARCH OBJECTIVES

Determine the relative distribution, abundance and diversity of forest songbirds and small mammals within the Little Mecatina River (treatment site) and the St. Augustin River (control site).
Quantify the structure and composition of the main habitat types within the two river valleys.
Relate songbird and small mammal abundance (or presence and absence) and diversity to habitat types and structures.

Field staff use Zodiak to navigate river

Scope the viability of intensive red squirrel telemetry studies and the potential for studies on other wildlife taxa.
Obtain a measure of noise dosage in the two river valleys.

STUDY AREAS
The two rivers selected for the pilot study were large fourth order rivers that run through southern Labrador and eastern Québec and into the Gulf of Saint Lawrence. The research was conducted along 20 kilometer sections of the Little Mecatina River (51º43'N, 60º07'W) and the St. Augustin River (51º57'N, 59º20'W), which were located approximately 160 km south of Goose Bay, Labrador in the transitional zone between the Boreal Shield and the Taiga Shield ecoregions. The two study areas were approximately 60 km apart and shared similar physical geography.

Location of Study Sites along the Little Mecatina and St. Augustin Rivers

The Little Mecatina River served as the experimental site since it was located within the Military Training Area and was used extensively for low-level military jet training. The St. Augustin River was located outside of the Military Training Area and acted as the control site.

RESEARCH ACTIVITIES
The river valleys under investigation consisted of a mosaic of open conifer-lichen forest, closed conifer forest, deciduous forest, mixed deciduous and coniferous forest, burned areas, and wetlands. The topography of both river valleys included a combination of steep sided valleys, rolling hills and plateaus. The research was conducted in the two major habitat types that occur along the river valleys, open conifer-lichen forest and closed conifer forest.

A dense canopy of black spruce and balsam fir trees with an understory of young trees, shrubs, forbs and mosses characterized the closed conifer forests. The open conifer-lichen forests were areas of re-growth where forest fires once burned in the river valleys. They were composed primarily of large expanses of caribou lichen, Labrador tea, other shrub species and sparsely populated black spruce trees.

Closed conifer forest

Open conifer-lichen forest with distinct riparian zone along the rivers edge

Each habitat type was composed of a riparian area and an upland area. A Riparian area is a portion of the landscape that is influenced by the shorelines of lakes, rivers and streams and supports plant and animal communities that are distinct from those in the upland zone, which are not influenced by water bodies. The riparian areas could often be recognized by a band of speckled alder along the river's edge and habitat characteristics similar to that of closed conifer forests.

The focus of this year's pilot study was to obtain general information on the habitat composition and associated fauna within two selected river valleys in Quebec-Labrador. Research activities in the river valleys included: forest songbird censuses, small mammal trapping, habitat sampling and incidental observations of red squirrels. Other wildlife species encountered (including sign) were also recorded to assess the potential for future research on additional wildlife taxa.

Forest Songbird Census

Forest songbird censuses were conducted to determine the composition and abundance of breeding songbirds in the river valleys and make comparisons of songbirds between open conifer-lichen forests and closed conifer forests and between riparian and upland sites. Forest songbird censuses were conducted during the months of June and July, which was the height of the breeding season in Quebec-Labrador.

Field Technician Kathy Hogan conducts a bird survey at a riparian census point

Transects were established in open conifer-lichen and closed conifer habitats along each river with paired census stations situated at 50 meters from the rivers edge, in the riparian zone, and 300 meters from the rivers edge in the upland forest. Birds were surveyed at each census point for a five-minute sampling period between dawn and 10:30 am using a fifty-meter fixed radius point count method. Upon arrival to the census point, observers remained inactive for at least two minutes before beginning the survey in order to allow the birds to resume normal activity. During the survey, observers recorded all birds seen or heard, including those that flew over and other incidental observations of wildlife, such as red squirrel presence. Each census point was surveyed twice over the four-week sampling period.

Small Mammal Trapping

Small mammal trapping was conducted to determine the composition and abundance of small mammals in the river valleys and to make comparisons of small mammals between open conifer-lichen forests and closed conifer forests and between riparian and upland sites. Small mammal trapping was conducted throughout the month of August, with the first two weeks being spent at the Little Mecatina River and the following two weeks being spent at the St. Augustin River.

Field Biologist Corinne Wilkerson checks traps

Small mammal sampling was carried out on a sub-sample of selected songbird survey point pairs. A 4 x 5 trapping grid centered on the survey point was established that consisted of 2 traps per station and a spacing interval of 12 meters. Standard Victor snap traps were used which were set and checked for three subsequent days. Traps were baited with a mixture of peanut butter and rolled oats. Captured animals were identified to species and measurements were taken to determine age, sex, mass and reproductive status.

Habitat Sampling

The vegetation characteristics of an area provide an indication of the habitat available for wildlife, such as, suitable sites for nesting and denning, and suitable plants for foraging. Vegetation sampling was conducted within a 0.1-hectare circular plot situated at the center of all small mammal trapping grids. Within this plot all live trees, snags and shrubs were recorded.

Field Technician Kathy Hogan measuring ground vegetation

For live trees, species were identified and measurements of diameter at breast height (dbh), and relative height were recorded. Measurements for snags, which are standing dead trees, included dbh, relative height and a decay classification. Ground vegetation was measured in one meter square quadrats randomly distributed throughout the circular plot and recorded as percent composition of lichen, moss, woody plants, non-woody plants, etc. Coarse woody debris was measured on each trapping grid by recording the dbh and length of downed wood that crossed the middle and outer transects of the trapping grid.

Red Squirrel Observations

Red Squirrel

Incidental observations of Red Squirrels were recorded throughout June, July and August. This data will indicate the relative distribution of red squirrels among habitat types in the river valleys and will assess the viability of future research on this species. During the five-minute bird censuses in June and July, researchers recorded red squirrel presence.

Red squirrel activity was again recorded in August while completing the downed wood transects on the small mammal trapping grids and during habitat sampling. Summer field technician, Kathy Hogan will use the collected data for her B.Sc. F. thesis at the University of New Brunswick.

NOISE MONITORING

Programmable logging sound meter used to measure noise levels at the study site

Over the course of the study, sound pressure levels were collected using a programmable logging Sound Level Meter. The sound meter records the average background noise and registers maximum noise levels reached during a flight disturbance. The noise measurements will provide a measure of the increase in noise levels associated with overflights and provide a relative measure of the amount a noise disturbance the treatment site (the Little Mecatina River Valley) is subjected to.

MILITARY OVERFLIGHTS

Low-level flight training involves navigating and maneuvering jet aircraft at subsonic speeds from 30 to 300 meters above ground level. Since 1981, military low-level jet aircraft training has been conducted annually in a 130,000-km2 portion of the Quebec-Labrador peninsula. The current training program typically involves 5000 to 6000 flights per year between the months of April and October.

Jet overflight at the Little Mecatina River

The Little Mecatina study area is located within the Military Training Area of Quebec-Labrador and is known to receive a high dose of military overflights. Data obtained from flight tracks mapped by the Department of National Defence will provide a measure of jets in proximity to the Little Mecatina River and will allow the development of a monthly and daily schedule of jet activity on the Little Mecatina River.

HIGHLIGHTS OF RESULTS FOR 2001
The Institute plans to make comparisons of songbird and small mammal abundances between the two river valleys and among differing habitats within the river valleys. Analyses of collected data are now ongoing and preliminary results will be available over the upcoming months.

Songbirds
A total of 53 species were detected during the songbird census. The most common species detected were Slate-colored Junco, Swainson's Thrush and Ruby-crowned Kinglet.

Slate-colored Junco

Swainson's Thrush

Ruby-crowned Kinglet

List of birds detected at Little Mecatina and St. Augustin Rivers:

Ruffed Grouse (Bonasa umbellus)2
Spruce Grouse (Falcipennis canadensis)
Spotted Sandpiper (Actitis macularia)
Common Nighthawk (Chordeiles minor)1
Belted Kingfisher (Ceryle alcyon)
Northern Flicker (Colaptes auratus)
Hairy Woodpecker (Picoides villosus)2
Three-toed Woodpecker (Picoides tridactylus)1
Black-backed Woodpecker (Picoides arcticus)1
Olive-sided Flycatcher (Contopus cooperi)2
Yellow-bellied Flycatcher (Empidonax flaviventris)
Alder Flycatcher (Empidonax alnorum)1
Philadelphia Vireo (Vireo philadelphicus)1
Blue-headed Vireo (Vireo solitarius)
Blue Jay (Cyanocitta cristata)1
Gray Jay (Perisoreus canadensis)
Common Raven (Corvus corax)2
Tree Swallow (Tachycineta bicolor)2
Boreal Chickadee (Poecile hudsonica)
Red-breasted Nuthatch (Sitta canadensis)
Winter Wren (Troglodytes troglodytes)
Golden-crowned Kinglet (Regulus satrapa)
Ruby-crowned Kinglet (Regulus calendula)
Swainson's Thrush (Catharus ustulatus)
Hermit Thrush (Catharus guttatus)
American Robin (Turdus migratorius)
Bohemian Waxwing (Bombycilla garrulous)
Cedar Waxwing (Bombycilla cedrorum)
Tennessee Warbler (Vermivora peregrina)
Magnolia Warbler (Dendroica magnolia)
Yellow-rumped Warbler (Dendroica coronata)
Black-and-White Warbler (Mniotilta varia)2
Blackburnian Warbler (Dendroica fusca)
Black-throated Green Warbler (Dendroica virens)
Bay-breasted Warbler (Dendroica castanea)
Blackpoll Warbler (Dendroica striata)
Palm Warbler (Dendroica palmarum)
Yellow Warbler (Dendroica petechia)
Wilson's Warbler (Wilsonia pusilla)
Ovenbird (Turdus migratorius)1
Northern Waterthrush (Seiurus noveboracensis)
American Redstart (Setophaga ruticilla)1
Chipping Sparrow (Spizella passerina)
Fox Sparrow (Passerella iliaca)
Lincoln's Sparrow (Melospiza lincolnii)2
White-throated Sparrow (Zonotrichia albicollis)
White-crowned Sparrow (Zonotrichia leucophrys)
Slate-colored Junco (Junco hyemalis)
Rusty Blackbird (Euphagus carolinus)2
Purple Finch (Carpodacus purpureus)1
White-winged Crossbill (Loxia leucoptera)
Pine Grosbeak (Pinicola enucleator)1
Pine Siskin (Carduelis pinus)

1 only detected at St. Augustin River
2 only detected at Little Mecatina River

Small Mammals
A total of 8 species were captured during the small mammal trapping. The most common species captured were the Red-backed Vole, Masked Shrew, Woodland Jumping Mouse and Meadow Jumping Mouse.

Field staff Kathy Hogan and Coreen Michelin conduct dissections on captured small mammals

Field Technician Kathy Hogan weighs a
Red-backed Vole

List of mammals captured at Little Mecatina and St. Augustin Rivers:

Masked Shrew (Sorex cinereus)
Northern Flying Squirrel (Glaucomys sabrinus)2
Deer Mouse (Peromyscus maniculatus)1
Red-backed Vole (Clethrionymys gapperi)
Heather Vole (Phenacomys intermedius)1
Meadow Vole (Microtus pennsylvancius)1
Meadow Jumping Mouse (Zapus hudsonius)
Woodland Jumping Mouse (Napaeozapus insignis)1

1 only detected at St. Augustin River
2 only detected at Little Mecatina River

Habitat
· Trees
All tree species within the vegetation sampling plots were identified and measured. The following is a list of the tree species encountered in the sampling plots, however, it is not a comprehensive list of all trees present in the river valleys.

Black Spruce (Picea mariana)
Balsam Fir (Abies balsamea)
Choke Cherry (Prunus virginiana)
Dogwood (Cornus spp.)
Balsam Poplar (Populus balsamifera)
Speckled Alder (Alnus rugosa)
Trembling Aspen (Populus tremuloides)
White birch (Betula papyrifera)
White spruce (Picea glauca)
Yellow birch (Betula lutea)
Tamarack/Larch (Larix laicina)
Willow (Salix spp.)

· Shrubs
Shrubs were primarily counted by number of stems within the vegetation sampling plot, however, species were identified whenever possible. The following is a list of shrub and small tree species identified on the sampling plots, however, it is not a comprehensive list of all shrubs present in the river valleys.

Labrador Tea

Bog Laurel

Labrador Tea (Ledum groenlandicum)
Bog Laurel (Kalmia polifolia)
Lambkill/Sheep Laurel (Kalmia angustifolia)
Dogberry (Sorbus spp.)
Leatherleaf (Chamaedaphne calyculata)
Dwarf Birch (Betula spp.)
Currant (Ribes spp.)
Hawthorn (Crataegus spp.)
Red Raspberry (Rubus idaeus)
Mountain Maple (Acer spicatum)

ADDITIONAL INFORMATION

To see more photos from the River Valley Ecosystem research Project, please check out the IEMR Photo Album
To search for reports and publications relating to the River Valley Ecosystems project, please search the IEMR Library Keywords: river valley, song birds, small mammals
For web sites related to songbirds and small mammals please refer to IEMR Links (River Valley Ecosystem Project)

SELECTED READING LIST

Darveau, M., P. Beauchesne, L. Bélanger, J. Huot and P. Larue. 1995.
	Riparian Forest Strips as habitat for breeding birds in boreal forest. Journal of Wildlife Management. 59(1): 67-78.
Farrar, J.L. 1995. Trees in Canada. Fitzhenry and Whiteside Limited,
	Markham, Ontario.
Krebs, C.J. and I. Wingate. 1985. Population fluctuations in the small
	mammals of the Kluane Region, Yukon Territory. Canadian Field-Naturalist 99(1): 51-61.
McGarigal, K. and W.C. McComb. 1992. Streamside versus upslope
	breeding bird communities in the central Oregon coast range. Journal of Wildlife Management 56(1):10-23.
Ryan, A. G. 1995. Native Trees and Shrubs of Newfoundland and
	Labrador. Parks Division, Department of Environment and Lands, Province of Newfoundland.
Simon, N.P.P., F.E. Schwab, and A.W. Diamond. 2000. Patterns of
	breeding bird abundance in relation to logging in western Labrador. Canadian Journal of Forest Research 30:257-263.
Thompson, I.D. and A. L. Macaulay. 1987. Comparative efficiency of
	new and old-style Museum Special traps in capturing small mammals. Canadian Field-Naturalist 101(4): 608-610.
Thompson, I.D., H.A. Hogan, and W.A. Montevechhi. 1999. Avian
	Communities of Mature Balsam Fir Forests in Newfoundland: Age-Dependence and Implications for Timber Harvesting. The Condor 101:311-323.
Vickery, W.L. 1981. Habitat use by northeastern forest rodents. The
	American Midland Naturalist 106(1): 111-118.
Vickery, W.L., S.L. Iverson, S. Mihok, and B. Schwartz. 1989.
	Environmental variation and habitat separation among small mammals. Canadian Journal of Zoology 67: 8-13.
Watts, I. 2000. An Introduction to Wildflowers and Berries of the Upper
	Lake Melville Region, Labrador (pamphlet). North West River, Labrador.
Whitaker, D.M. and W.A. Montevecchi. 1999. Breeding bird assemblages
	inhabiting riparian buffer strips in Newfoundland, Canada. Journal of Wildlife Management 63(1): 167-179.
Williams, D.F. and S.E. Braun. 1983. Comparison of pitfall and
	conventional traps for sampling small mammal populations. Journal of Wildlife Management 47(3): 841-845.

River Valley Field Crew: (l to r)
Kathy Hogan, Tina Newbury, Greg Johnson,
Colin Jones, Coreen Michelin, Ted Pardy, Roland Kemuksigak
(Missing: Corinne Wilkerson)

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