Calving photocensus of the Rivière George Caribou Herd and comparison with an independent census

Vertical photographs of the calving grounds have been used since 1984 to estimate the caribou (Rangifer tarandus) population of the Rivière George Caribou Herd (RGCH) in Northern Québec and Labrador. In spite of large confidence intervals, the 1984 and 1988 estimates suggested that the herd stabilized at more than 650 000 caribou (fall estimate including calves) making the RGCH the largest caribou herd in the world. Between 1984 and 1990, studies suggested that the former rapid growth of the herd deteriorated the calving and summer habitats. This poor habitat quality affected physical condition, pregnancy rate and calf survival. It was important to have a valid estimate of the herd size and a photocensus was done in June 1993. Contrary to previous censuses, a slightly different sampling design was applied in 1993. Two methods were used to estimate the number of females in the June population. In the first method, the number of females was derived from the estimated number of calves on the photographs and from the June female/calf ratio. The second method was used in the previous census and is based on the number of adults on the photos and on the June female/adult ratio. It is suggested that the first method of estimating female abundance in June is better due to sampling problems associated with a strong adult sex segregation during calving. From the first method, the herd size in October 1993 was estimated at 583 829 adults (±33.79%) and at 749 869 caribou including calves (±33.15%) while the second method provided estimates of 764 221 adults (±23.55%) and 981 565 caribou including calves (±22.64%). It was possible to compare those population estimates with an independent census. In July 1993, an oblique photocensus of the post-calving aggregations was conducted by Russell et al. (1996). A new analysis of their raw data provided an estimate of 608 384 adults (±14.35%). Both estimates from the June and July photocensus were combined. From the first and second method respectively, combined herd size estimates were 775 891 (±13.40%) and 823 375 (±12.36%) caribou including calves. The management implications are discussed and it is emphasized that the herd is still underharvested

La qualité des interactions en classe de maternelle 4 ans à mi-temps au Québec

Cet article vise à : 1) évaluer la qualité des interactions en classe de maternelle 4 ans à mi-temps au Québec (N = 70 classes) ; et 2) examiner la structure factorielle originale du Classroom Assessment Scoring System Pre-K (CLASS Pre-K) dans ce même contexte éducatif. D’une part, en convergence avec les écrits dans le domaine, les résultats démontrent que les scores associés aux domaines du soutien émotionnel et à l’organisation de la casse s’avèrent de niveaux modérés, comparativement à celui relié au soutien à l’apprentissage qui se situe à un faible niveau. D’autre part, les analyses factorielles confirmatoires n’ont pas permis de corroborer la structure factorielle originale du CLASS Pre-K. Néanmoins, lorsqu’une des dimensions de l’outil est retirée, plus précisément celle de la prise en considération du point de vue de l’enfant, le modèle s’ajuste mieux aux données du présent échantillon. Les analyses de validité convergente confirment ce résultat. Toutefois, d’autres analyses devraient être effectuées auprès d’un plus grand échantillon et en privilégiant d’autres méthodes, de manière à déterminer si la dimension « prise en considération du point de vue de l’enfant » devrait bel et bien être retirée du modèle. Pour l’instant, la structure factorielle originale devrait être maintenue afin d’étudier la qualité des interactions en contextes éducatifs pendant la petite enfance

La qualité des interactions en classe de maternelle 4 ans à mi-temps au Québec

Cet article vise à : 1) évaluer la qualité des interactions en classe de maternelle 4 ans à mi-temps au Québec (N = 70 classes) ; et 2) examiner la structure factorielle originale du Classroom Assessment Scoring System Pre-K (CLASS Pre-K) dans ce même contexte éducatif. D’une part, en convergence avec les écrits dans le domaine, les résultats démontrent que les scores associés aux domaines du soutien émotionnel et à l’organisation de la casse s’avèrent de niveaux modérés, comparativement à celui relié au soutien à l’apprentissage qui se situe à un faible niveau. D’autre part, les analyses factorielles confirmatoires n’ont pas permis de corroborer la structure factorielle originale du CLASS Pre-K. Néanmoins, lorsqu’une des dimensions de l’outil est retirée, plus précisément celle de la prise en considération du point de vue de l’enfant, le modèle s’ajuste mieux aux données du présent échantillon. Les analyses de validité convergente confirment ce résultat. Toutefois, d’autres analyses devraient être effectuées auprès d’un plus grand échantillon et en privilégiant d’autres méthodes, de manière à déterminer si la dimension « prise en considération du point de vue de l’enfant » devrait bel et bien être retirée du modèle. Pour l’instant, la structure factorielle originale devrait être maintenue afin d’étudier la qualité des interactions en contextes éducatifs pendant la petite enfance

AERIAL SURVEYS OF MOOSE POPULATIONS IN SMALL CENSUS ZONES

We developed a simple, precise and relatively inexpensive technique to estimate moose (Alces alces) populations in small census zones (< 1500-2000 km2) such as parks and wildlife reserves. A two-phase sampling plan was adopted. In phase 1, we used fixed-wing aircraft to survey the entire area using flight lines spaced 500 m apart in order to locate track networks, draw them on 1:50,000 topographic maps, and determine their area. In phase 2, a sample of the identified track networks was intensively searched by helicopter to count moose. total population was estimated by extrapolating the mean number of moose per track network to the total number of networks counted in phase 1. We compared three approaches to estimate the mean number of moose per track network and its variance: a direct estimation using the arithmetic mean per track network, and two methods that accounted for the size of track networks (quotient and regression estimations). The regression estimation model provided the most precise estimates. A confidence interval of 20% (α = 0.10) can be achieved by counting moose on 30 to 50 % of the track networks. This two-phase approach can reduce survey costs by 25-35 percent as compared to the usual total count preciously used in small census zones

QUÉBEC MOOSE AERIAL SURVEYS: METHODS TO ESTIMATE POPULATION CHARACTERISTICS AND IMPROVED SAMPLING STRATEGIES

We present methods to estimate various parameters of moose populations using stratified random sampling and double sampling. Québec's winter moose population outside parks and reserves between 1987 and 1991 was estimated at 52,543 individuals. The confidence interval of this estimate is 4,917 moose, which represents a relative error of 9 % (α = 0.10). sex ratio is often imbalanced, with males representing less than 35 % of the adult segment. We noticed important regional variability in productivity. Southern populations were the most productive (> 60 calves / 100 females), whereas the western and northern ones were the least productive (22-44 calves / 100 females). We checked if a flight over the same sample plots could raise the power of statistical comparisons between two aerial surveys. We compared term to term moose densities in fifty-seven 60 km2 sample plots, from two independent aerial surveys, spaced 3 to 6 years apart. Based on the 6 territories analyzed, the surface are of the track networks, as well as the number of moose per plot, which represent two density indicators, were not generally correlated between the two surveys. Variance component analysis, however, showed that the variance due to sample plots was between 4 and 72 % in the 6 territories under analysis. This shows that repeated survey design could be useful to detect changes in population densities between two aerial surveys