Calgary Bird Banding Society - Dedicated to the Research and Conservation of Birds

Migration Monitoring

Neotropical migrants are birds that breed in the Nearctic biogeographic realm and winter in the Neotropics. The Neotropical migratory bird system involves some 5-10 billion birds of over 150 species (Greenberg 1992). Trends in data from the Breeding Bird Survey indicate that many Neotropical migrants in North America may be decreasing. Although destruction of tropical forests on the wintering grounds has been implicated in declines, increasing concern is being raised about the potential effect of accelerated land-use changes on breeding grounds.

The main objective of CBBS is to conduct migration monitoring and other banding-based studies at Inglewood Bird Sanctuary (IBS), a federal Migratory Bird Sanctuary. IBS has long been known as an important migration site for Neotropical migrants. Located within 80-km of the Rocky Mountains, the site is an integral component of the Canadian Migration Monitoring Network coordinated and administered by Bird Studies Canada.
Click here to download  Migration monitoring and trends - BSC - Oct 2007
Click here to download  CMMN Stations Map (2007)



METHODOLOGY

Daily Constant-Effort Mist-netting
Both spring and fall migration of Neotropical migrants is monitored at Inglewood Bird Sanctuary (IBS). IBS's 35 hectares includes mature riverine balsam poplar forest known for its number and diversity of songbirds during spring and fall migration (Sherrington 1975, Elphinstone 1990). Constant-effort mist-netting (i.e. constant number of nets in permanent locations for constant time period each day) and collection of associated morphometric and other data (e.g. age, sex, wing chord, weight, fat reserves, capture net, time of capture) from each bird captured was carried out each day, weather permitting, during spring and fall migration. Twelve 12-m long x 30-mm mesh mist-nets are operated in permanent net lanes for approximately 6-hours each day beginning at sunrise. The standardized daily constant-effort mist-netting protocol used at IBS was developed from procedures outlined in McCracken et al. 1993 (A manual for monitoring bird migration), Hagan et al. 1994 (Recommended methods for monitoring bird migration) and Hussell and Ralph 1996 (Recommended methods for monitoring bird populations by counting and capture of migrants).
Mist-netting produces a daily count of new captures for each species from which trends are calculated.

Daily Estimated Totals
The daily estimated totals (DETs) represent the total number of birds, by species, detected at the IBS migration monitoring site each day. Each DET incorporates capture data as well as a standardized census and any casual observations made during banding operations. The DETs, after removal of probable and known stopovers (PKS), give an overall description of bird migration. DET is secondary, and inferior to, mist-netting as a monitoring measure at IBS. If high capture rates and/or personnel shortage create a risk to the welfare of the birds, a census (and therefore a DET) is not done.

In 2007, CBBS conducted a pilot spring migration monitoring program at Dinosaur Provincial Park.

Monitoring Avian Productivity
and Survivorship (MAPS) Program

The Monitoring Avian Productivity and Survivorship (MAPS) Program was created by The Institute for Bird Populations in 1989 to assess and monitor the vital rates and population dynamics of over 120 species of North American landbirds in order to provide critical conservation and management information on their populations. The MAPS Program utilizes constant-effort mist netting and banding at a continent-wide network of monitoring stations staffed by both professional biologists and highly trained volunteers.   click for the Institute for Bird Populations website

North America is divided into eight major regions based on biogeographical and meteorological considerations, and each region has, within it, target species. IBS falls into the Northwest Region whose target species are:

• Dusky Flycatcher
• Western Flycatcher complex
• Swainson's Thrush
• American Robin
• Warbling Vireo
• Orange-crowned Warbler
• Yellow Warbler
• MacGillivray's Warbler
• Wilson's Warbler
• Song Sparrow
• Lincoln's Sparrow
• "Oregon" Dark-eyed Junco

All of these species have been captured at IBS although only American Robin, Warbling Vireo, Yellow Warbler, Song Sparrow, and Lincoln's Sparrow are breeders. (click for Table from the 2006 ATR)  MAPS data is provided to the Institute for Bird Populations in Point Reyes, CA where it is integrated with data from the over 500 other North American stations.

Objectives

The overall objective of the MAPS Program is to contribute to an integrated avian population monitoring system for selected North American landbirds. The indices and estimates obtained:

determine annual changes and, ultimately, longer-term trends in population and demographic parameters of target species in each region;

relate these trends to readily-measured environmental co-variates such as climatic factors, habitat type, and management practice; and

refine current population models and develop new ones.

Northern Saw-whet Owl Monitoring Project

Since 2004, the CBBS has been monitoring migrating Northern Saw-whet Owls (Aegolius acadicus) (NSWO) at a site in the foothills southwest of Calgary. This site has proven itself as a good location for monitoring migration of Northern Saw-whet Owls. Monitoring sites for this species are well established in eastern North America but sparse in western North America.

click here for full size Project Owlnet map

Monitoring begins mid September and continues through the end of October. A continuous audiolure (recording of NSWO calls  *click to hear it) is played to enhance capture rate. It is placed at the center of an array (double H) of five 12-m long x 60-mm mesh mist-nets. The array is beneath a thick canopy of mature spruce trees. The area has been subject to cattle grazing and the understory and tree branches as high as a cow can rub are absent. The audiolure commences approximately 0.5-hrs after sunset and continues for 4-hrs, weather and other factors permitting. Nets are checked at least every 0.75-hrs by a Bander-in-Charge (BIC) and 1 or more volunteers. Sex, age and morphometric data are collected on all owls captured. Basic weather data (wind direction and speed, sky conditions and temperature) is noted at start and finish each evening.
*audio clip courtesy Barb and Jim Beck

This year between 15 Sept and 31 October CBBS banded 147 NSWOs for a capture rate of 0.23 owls/net-hr. Comparable numbers from 2004, 2005, 2006 are 0.25, 0.29 and 0.27 respectively.

Costa Rica Projects

Migration Monitoring at Las Caletas, Costa Rica

A migration monitoring site on the Osa Peninsula on the Pacific coast of Costa Rica was identified in 1998 and a pilot project was initiated in 2002 and continued in 2003. A full migration monitoring program was initiated in 2004 and continued in 2005 and 2007 to monitor Neotropical migrants on their northward migration through Central America.

The migration monitoring site is located on the Pacific coast of southwest Costa Rica on the Osa Peninsula just north of Corcovado National Park in the vicinity of the Las Caletas ecotourism lodge. The lodge is located on the south coast of Drake Bay, a few kilometres southwest of the small village of Agujitas. The lodge is on a hill looking north over the Pacific Ocean. The monitoring station is 200 metres further uphill south of the lodge.

Migration monitoring methods used at Las Caletas are similar to those at IBS. Constant-effort mist-netting and collection of associated morphometric and other data (e.g. age, sex, wing chord, weight, fat reserves, capture net, time of capture) from each bird captured was carried out on each day, weather permitting. Mesh mist-nets (12-m long x 30-mm) were operated for approximately 6 hours each day beginning at sunrise (~ 0530 to 1130). USFWS aluminum bands were applied to migrants while CBBS-purchased bands were applied to species resident in the area, including hummingbirds.

MoSI (Monitoreo De Sobrevivencia Invernal)

In 2006 and 2007, CBBS undertook a pilot initiative based on the MoSI program of the Institute for Bird Populations primarily aimed at quantifying over-winter survival of Neotropical migrants.

MoSI Program Goals

MoSI is designed to address monitoring, research, and management goals. The monitoring goal of MoSI is to provide estimates of monthly, overwintering, and annual survival rates and indices of late winter physical condition for a suite of 25 landbird species for a variety of habitats and geographic regions. Research goals of MoSI include (1) the statistical modeling of survival and physical condition as functions of age, sex, habitat, geographic location, and weather; (2) linking winter population parameters with breeding season vital rates and population trends; and (3) the development of predictive population models. Management goals of MoSI are to (1) use research results to develop strategies for reversing population declines and maintaining healthy populations, and (2) evaluate implemented management actions through an adaptive management framework. Like MAPS, MoSI calls for the establishment of a geographically extensive network of mist-netting and banding stations to meet these program objectives. The establishment of the MoSI network will also facilitate the collection of feathers for molecular analyses that link breeding and wintering populations. (click here Institute of Bird Populations website)

MoSI Field Protocol

Mangrove Warbler
during MoSI 3 Mar 06

The basic MoSI field protocol calls for five monthly (November through March) pulses of mist net operation on a 20-ha study area (the MoSI station) established in a habitat of interest where at least one MoSI target species can be captured in substantial numbers. Each pulse of mist netting consists of operating about 16 nets for two or (preferably) three consecutive days, yielding 10-15 days of netting during the five-month winter period.

Stable Isotope Ecology

Techniques are being developed to identify the geographic origin of birds captured at CMMN sites using stable isotopes. This project offers the possibility of confirming the hypothesis that CMMN sites monitor birds from a wide area north-west of their respective locations. Preliminary results involving 1999 samples from Delta Marsh Bird Observatory and Atlantic Bird Observatory indeed indicated that CMMN stations are capturing birds from a broad area, not simply from a small region close to the station.
Click here to download Tracking bird movements using stable isotopes by K. Hobson (Oct 2007)

Inglewood Bird Sanctuary

To investigate the origin of birds captured at IBS during the fall migration, feather material was collected from 54 resident and migrant birds during 2003. A total of 919 feather samples were collected from 28 species at IBS during 2004. A large subset of these samples has been analyzed and interpretation is underway in an effort to comprehensively characterize the breeding and/or natal areas of origin for species monitored at IBS.

Las Caletas, Costa Rica

Manuscripts have been accepted for publication in AUK and The Wilson Journal of Ornithology, both peer-reviewed journals, based on 109 Swainson's Thrush retrices collected at Las Caletas in 2004. These papers examine breeding destinations and spring migration patterns and spring migratory stopover respectively.

Mourning/MacGillivray's Warbler Research

Since 1995, CBBS has been gathering additional morphometric and plumage data on Mourning and MacGillivray's Warblers. Immatures and females of these two species can be very difficult to identify. Birds of these two species captured at IBS exhibit considerable overlap in the flat wing minus tail measurement and plumage characteristics typically used to identify the two species. Geographically, IBS is situated near the overlap zone of these two species and attracts sufficient numbers of each to fuel a research project. CBBS may be capturing hybrid Mourning/MacGillivray's Warblers.

With the assistance of other CMMN stations particularly Mackenzie Bird Observatory but also Last Mountain Bird Observatory and Delta Marsh Bird Observatory as well as data personally gathered by Douglas Collister in Manitoba and Alberta, CBBS is compiling data of known pure Mourning Warblers and MacGillivray's Warblers. It is hoped that with sufficient data, CBBS can determine whether captured birds at IBS likely represent hybrids or are simply a reflection of the identification captured between these two species.