scholarly journals Annual and Seasonal Variation in Shorebird Abundance in the St. Lawrence River Estuary during Fall Migration

2018 ◽  
Vol 131 (3) ◽  
pp. 203-214 ◽  
Author(s):  
Yves Turcotte ◽  
Jean-Francois Lamarre ◽  
Joel Bety
Keyword(s):  
General Trend ◽  
River Estuary ◽  
Abundant Species ◽  
Western Hemisphere ◽  
Ecological Value ◽  
Reserve Network ◽  
Semipalmated Sandpiper ◽  
Peak Abundance ◽  
Effective Conservation ◽  
St Lawrence River

Many north American shorebird populations are declining. it is therefore urgent to identify major sites used during their annual cycle to achieve effective conservation measures. our objective was to expand some aspects of the knowledge base needed to assess the ecological value of the St. Lawrence River Estuary for shorebird conservation. Here, we present the results of the most intensive shorebird survey ever conducted in the St. Lawrence River Estuary during fall migration. Surveys were conducted between St-Jean-Port-Joli and St-Simon-sur-Mer, Quebec, Canada, in 2011 and 2012, from late June/early July through late november, corresponding to the migration period of all species potentially present in the study area. The Semipalmated Sandpiper (Calidris pusilla) was one of the two most abundant species during both years of our study (most abundant species, followed by Dunlin [Calidris alpina] and Black-bellied Plover [Pluvialis squatarola] in 2011; second to Blackbellied Plover in 2012). Considering the entire shorebird community, abundance of individuals peaked in early September. Peak abundance occurred earlier for adults than for juveniles. For most species, juveniles largely outnumbered adults. Juveniles were relatively less abundant in 2012 than in 2011. This reflected a general trend observed in northeastern north America between those years, suggesting a lower breeding success in 2012. Given its importance as a staging site for juvenile birds (study area used annually by up to a few hundred thousand shorebirds) and therein, its conservation value, we recommend that the St. Lawrence River Estuary should be included within the Western Hemisphere Shorebird Reserve network.

Staging ecology of Semipalmated Plover (Charadrius semipalmatus) and Semipalmated Sandpiper (Calidris pusilla) juveniles in the St. Lawrence River Estuary during fall migration

2013 ◽  
Vol 91 (11) ◽  
pp. 802-809 ◽  
Author(s):  
Yves Turcotte ◽  
Jean-François Lamarre ◽  
Joël Bêty
Keyword(s):  
Length Of Stay ◽  
Body Mass ◽  
Atlantic Coast ◽  
River Estuary ◽  
Fat Free Mass ◽  
The North ◽  
Semipalmated Sandpiper ◽  
Calidris Pusilla ◽  
Charadrius Semipalmatus ◽  
St Lawrence River

The acquisition of body reserves by migrating shorebirds at specific staging sites is critical for reaching their breeding or wintering grounds. As many North American shorebird populations are declining, major staging sites need to be identified for effective conservation plans. Changes in body mass of Semipalmated Plover (Charadrius semipalmatus Bonaparte, 1825) and Semipalmated Sandpiper (Calidris pusilla (L., 1766)) juveniles, as well as length of stay and daily movements by Semipalmated Plover juveniles during fall migration, were studied in the St. Lawrence River Estuary in southern Quebec, Canada. Most juveniles of both species captured early in the migration period weighed less than the estimated mean fat-free mass. Body mass increased steadily in juveniles of both species during staging. Mean body masses of birds captured in our study area were similar to or higher than those of juveniles of both species captured along the North Atlantic coast. Length of stay of radio-tracked Semipalmated Plover juveniles ranged from 2 to 28 days. Body mass at capture and length of stay were negatively associated, suggesting that individuals refuelled before resuming their migration. Overall, these results provide evidence that the St. Lawrence River Estuary is an important staging site for Semipalmated Plover and Semipalmated Sandpiper juveniles.

scholarly journals Relationship Among Breeding, Molting, and Wintering Areas of Male Barrow's Goldeneyes (Bucephala Islandica) in Eastern North America

The Auk ◽  
2002 ◽  
Vol 119 (3) ◽  
pp. 676-684 ◽  
Author(s):  
Michel Robert ◽  
Réjean Benoit ◽  
Jean-Pierre L. Savard
Keyword(s):  
North American ◽  
River Estuary ◽  
North American Population ◽  
American Population ◽  
Adult Males ◽  
Breeding Area ◽  
The North ◽  
Bucephala Islandica ◽  
The Mean ◽  
St Lawrence River

Abstract Little is known of the eastern North American population of Barrow's Goldeneyes (Bucephala islandica), which was recently listed as “of special concern” in Canada. In 1998 and 1999, we marked 18 adult males wintering along the St. Lawrence River, Québec, with satellite transmitters to document their breeding, molting, and wintering distribution and phenology, and to describe timing and routes of their spring, molt, and fall migrations. Thirteen males moved inland from the St. Lawrence River to breed; the spring migration averaged 5.9 days, and birds arrived on breeding areas on average 9 May. All breeding areas were inland, on the north shore of the St. Lawrence River estuary and gulf. Breeding areas averaged 64.8 km from the St. Lawrence corridor. Males stayed on their respective breeding area a mean of 34.5 days, and left on average 11 June. Twelve males were tracked to their molting areas, one of which stayed on its wintering area until 5 June and flew directly to its molting area. Their molt migration averaged 18.6 days, and the mean arrival date on molting areas was 30 June. All molting areas were located north and averaged 986 km from breeding areas. Four males molted in Hudson Bay, four in Ungava Bay, two in northern Labrador, one on Baffin Island, and one inland, near the Québec–Labrador border. The mean length of stay on the molting areas was 105.3 days, and the mean date of departure from molting areas was 4 October. All goldeneyes for which the radio still functioned during fall migration returned to winter in the St. Lawrence River estuary, on average 6 November. Our results refute the idea that the main breeding area of the eastern North American population of Barrow's Goldeneyes is located in northern Québec and Labrador and rather indicate that it is in the boreal forest just north of the St. Lawrence River estuary and gulf. They also indicate that Barrow's Goldeneye males undertake a genuine molt migration, and highlight the importance of molting areas because birds stayed there approximately four months each year.

Observations on the biology of Mansonia perturbans (Walker) (Diptera: Culicidae) in the Nova Scotia–New Brunswick border region

1980 ◽  
Vol 58 (11) ◽  
pp. 2084-2088 ◽  
Author(s):  
David J. Lewis ◽  
Gordon F. Bennett
Keyword(s):  
Nova Scotia ◽  
New Brunswick ◽  
Aquatic Plants ◽  
Adult Emergence ◽  
Abundant Species ◽  
Border Region ◽  
Immature Stages ◽  
Peak Activity ◽  
Peak Abundance

Aerial sweep netting of mosquitoes in the Nova Scotia – New Brunswick border region during the summers of 1973–1975 revealed that Mansonia perturbons (Walker) is the most abundant species in this region. This mosquito is univoltine; adult emergence commences in late June; peak abundance occurs about mid-July; peak activity of blood-seeking females occurs at or near darkness. Observations were made of swarming adults, and the immature stages were associated with at least seven species of aquatic plants. Mansonia perturbans appears to have become a relatively recent pest in this region.

scholarly journals Species composition and diel variation of a butterfly taxocene (Lepidoptera, Papilionoidea and Hesperioidea) in a restinga forest at Itapuã State Park, Rio Grande do Sul, Brazil

2006 ◽  
Vol 23 (2) ◽  
pp. 443-454 ◽  
Author(s):  
Maria O. Marchiori ◽  
Helena P. Romanowski
Keyword(s):  
Coastal Plain ◽  
General Trend ◽  
Rio Grande ◽  
Abundant Species ◽  
Butterfly Species ◽  
Diel Variation ◽  
Rio Grande Do Sul ◽  
Sandy Forest ◽  
Diversity Estimates ◽  
Hourly Variation

The composition and the hourly variation of butterfly species (Lepidoptera: Papilionoidea and Hesperioidea) throughout the day and the seasons was evaluated in a 1,000 m² patch of sandy forest (Restinga forest) on a coastal plain at Itapuã State Park (30º22'S, 51º02'W), Viamão, Rio Grande do Sul, from July 2001 to June 2002. Butterflies were sampled by scanning and focal observations (adapted from ALTMANN 1974) carried out at successive 45 minutes intervals. This methodology proved to be effective in recording the presence and activity of butterflies on a small area. A total of 108 observation hours yielded 326 butterflies from 41 species, 33 genera and five families. Nymphalidae was the most abundant family contributing with 74% of the total individuals. The most abundant species was Eunica eburnea Fruhstorfer, 1907 (Nymphalidae) with 45 individuals registered along the year. General diversity estimates were Dmg = 6.912, H' = 3.012 and d = 0.138. Although there were variations in the daily times of butterfly activity throughout the seasons, there was a general trend for higher activity during the morning period, between 9:00 and 11:45 h.

The influence of salinity on Scirpus americanus tidal marshes in the St. Lawrence River estuary, Québec

1985 ◽  
Vol 63 (5) ◽  
pp. 920-927 ◽  
Author(s):  
J. Deschênes ◽  
J.-B. Sérodes
Keyword(s):  
Fresh Water ◽  
Lower Limit ◽  
Brackish Water ◽  
Saline Water ◽  
River Estuary ◽  
Considerable Effect ◽  
Tidal Marshes ◽  
Brackish Waters ◽  
Scirpus Americanus ◽  
St Lawrence River

The amount of sodium in the aboveground part of the stalks of Scirpus americanus taken at the peak of biomass is a good indicator of the amount of salinity in the waters flooding the tidal marshes of an estuary. In fresh water, the Na concentrations remain below 10 000 and then increase sharply up to 20 000 – 30 000 mg/kg in brackish waters. Even though this plant can grow under brackish conditions, salinity has a considerable effect on the percentage of submersion it can withstand. Consequently, in the presence of saline water, the lower limit of the vegetation regresses towards the shore. In the case of fresh water, Scirpus americanus occupies the lower part of marshes up to an average of 75% of submersion, while in brackish water it extends to about 35% and then disappears when waters are more saline.

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