Impact of seed and seedling predation by small rodents on early regeneration establishment of black spruce

2003 ◽  
Vol 33 (12) ◽  
pp. 2362-2371 ◽  
Author(s):  
Mathieu Côté ◽  
Jean Ferron ◽  
Réjean Gagnon
Keyword(s):  
Seed Predation ◽  
Black Spruce ◽  
Habitat Type ◽  
Major Effect ◽  
Food Sources ◽  
Small Rodent ◽  
Small Rodents ◽  
Seedling Predation ◽  
Early Regeneration ◽  
The Impact

Black spruce (Picea mariana (Mill.) BSP) postdispersal seed and juvenile seedling predation by small rodents (Peromyscus maniculatus (Wagner), Clethrionomys gapperi (Vigor), and Phenacomys intermedius (Merriam)) was assessed in three boreal habitats over a 2-year period using an extensive exclosure–control experiment. Small rodent relative abundance was measured during six periods using snap trapping. We found that seed and juvenile seedling predation by small rodents varied according to habitat type and over time. Indeed, seed predation was higher in spruce–moss forests than in other habitats, notably during the winter of 2002. During this period, seedling predation was higher in recent burns. This period of higher seed and juvenile seedling predation corresponded to an increase in small rodent abundance in our study area. We suggest that seeds and juvenile seedlings can become important food sources for small rodents during winter when fresh and succulent vegetation is rare, as shown by results of seed predation. The impact of small rodents on the early regeneration of black spruce in the eastern Canadian boreal forest is thus an important factor to consider to better understand the forest regeneration process in this particular biome. Rodents can have a major effect on regeneration following a burn and can also contribute to poor seedling establishment from natural seed rain under mature cover.

scholarly journals The impact of small terrestrial mammals on beech (Fagus sylvatica) plantations in spruce monoculture

2007 ◽  
Vol 55 (5) ◽  
pp. 131-136 ◽  
Author(s):  
Luboš Purchart ◽  
Josef Suchomel
Keyword(s):  
Fagus Sylvatica ◽  
Forest Regeneration ◽  
Sorex Araneus ◽  
Clethrionomys Glareolus ◽  
Lepus Europaeus ◽  
Small Rodent ◽  
Apodemus Flavicollis ◽  
Small Rodents ◽  
Terrestrial Mammals ◽  
The Impact

Little is known about the impact of small terrestrial mammals on forest regeneration as yet. In order to determine the level of small rodent impact on artificial forest regeneration, 508 saplings have been researched in a spruce monoculture in the Drahany Uplands. With the objective to hone the interpretation of the data, small terrestrial rodents were trapped to help determine species spectrum. The occurrence of Apodemus flavicollis, Clethrionomys glareolus and Sorex araneus was verified. In 52 cases damage to the trunk caused by small rodents was monitored (10.1% of all saplings). 8 specimens (1.6%) had their branches nibbled and 9 saplings (1.8%) had tips of branches or trunk tops browsed. Browsing by Lepus europaeus – 423 (83.3%) of all damaged specimens was significant.

scholarly journals Seed predation by rodents and safe sites for large-seeded trees in a fragment of the Brazilian Atlantic forest

2009 ◽  
Vol 69 (3) ◽  
pp. 763-771 ◽  
Author(s):  
SRR. Pinto ◽  
AMM. Santos ◽  
M. Tabarelli
Keyword(s):  
Atlantic Forest ◽  
Seed Predation ◽  
Forest Edge ◽  
Northeastern Brazil ◽  
Small Rodent ◽  
Forest Fragments ◽  
Small Rodents ◽  
Seed Predator ◽  
Safe Sites ◽  
Adult Trees

Seed predation by small rodents is an emerging theme in the ecology of modified landscapes. Here we investigate the role played by the small rodent Oryzomys oniscus as a seed predator of large-seeded trees in a large remnant of the Atlantic forest - the Coimbra forest (3,500 ha), Alagoas state, northeastern Brazil. O. oniscus was captured and identified by setting twenty 500 m long transects, each one composed of 25 traps 20 m apart. This procedure resulted in 483 trap-nights set during a 20-mo period. We used 692 seeds (>15 mm length) from ten local large-seeded tree species for the seed predation trials that basically consisted of three treatments: one seed on the ground freely accessed by vertebrates (unprotected seed), one seed totally protected by an exclosure, and one partially-protected seed (exclosure just for medium-sized and large vertebrates). O. oniscus was captured throughout the Coimbra forest including forest edges (76 captures) and interior areas (67), and this small rodent was responsible for all seed predation visually documented inside exclosures. A 24 hours period of seed exposition permitted elevated rates of seed removal and predation. Seeds were much more removed/predated beneath fruiting trees, but rates varied according to the level of seed protection - 26.3% of predation among partially-protected versus 19.2% among unprotected seeds. Seeds suffered higher levels of seed predation/removal at the forest edge as well (up to 90%). In both habitats, most seeds (>84%) remained intact beneath trees without fruits, regardless of the level of seed protection. Our results suggest that O. oniscus may operate as an effective large-seed predator in forest fragments, in which adult trees without fruits constitute low resource spots and thereby provide, at least temporarily, safe sites for large seeds.

scholarly journals Population cycles and outbreaks of small rodents: ten essential questions we still need to solve

Oecologia ◽  
2020 ◽  
Author(s):  
Harry P. Andreassen ◽  
Janne Sundell ◽  
Fraucke Ecke ◽  
Stefan Halle ◽  
Marko Haapakoski ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Large Amplitude ◽  
Driving Forces ◽  
Population Cycles ◽  
Small Rodent ◽  
Small Rodents ◽  
Rodent Population ◽  
The World ◽  
Essential Questions ◽  
Rodent Populations

AbstractMost small rodent populations in the world have fascinating population dynamics. In the northern hemisphere, voles and lemmings tend to show population cycles with regular fluctuations in numbers. In the southern hemisphere, small rodents tend to have large amplitude outbreaks with less regular intervals. In the light of vast research and debate over almost a century, we here discuss the driving forces of these different rodent population dynamics. We highlight ten questions directly related to the various characteristics of relevant populations and ecosystems that still need to be answered. This overview is not intended as a complete list of questions but rather focuses on the most important issues that are essential for understanding the generality of small rodent population dynamics.

scholarly journals Beavers, Bugs and Chemistry: A Mammalian Herbivore Changes Chemistry Composition and Arthropod Communities in Foundation Tree Species

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 877
Author(s):  
Rachel M. Durben ◽  
Faith M. Walker ◽  
Liza Holeski ◽  
Arthur R. Keith ◽  
Zsuzsi Kovacs ◽  
...  
Keyword(s):  
Tree Species ◽  
Castor Canadensis ◽  
Habitat Type ◽  
Food Preferences ◽  
Woody Species ◽  
Juvenile Growth ◽  
Arthropod Community ◽  
Riparian Ecosystems ◽  
Arthropod Communities ◽  
The Impact

The North American beaver (Castor canadensis Kuhl) and cottonwoods (Populus spp.) are foundation species, the interactions of which define a much larger community and affect a threatened riparian habitat type. Few studies have tested the effect of these interactions on plant chemistry and a diverse arthropod community. We experimentally examined the impact of beaver foraging on riparian communities by first investigating beaver food preferences for one cottonwood species, Fremont cottonwood (P. fremontii S. Watson), compared to other locally available woody species. We next examined the impact of beaver foraging on twig chemistry and arthropod communities in paired samples of felled and unfelled cottonwood species in northern Arizona (P. fremontii) and southwestern Colorado (narrowleaf cottonwood, P. angustifolia James, and Eastern cottonwood, P. deltoides W. Bartram ex Marshall). Four major patterns emerged: (1) In a cafeteria experiment, beavers chose P. fremontii six times more often than other woody native and exotic species. (2) With two cottonwood species, we found that the nitrogen and salicortin concentrations were up to 45% greater and lignin concentration 14% lower in the juvenile resprout growth of felled trees than the juvenile growth on unfelled trees (six of seven analyses were significant for P. fremontii and four of six were significant for P. angustifolia). (3) With two cottonwood species, arthropod community composition on juvenile branches differed significantly between felled and unfelled trees, with up to 38% greater species richness, 114% greater relative abundance and 1282% greater species diversity on felled trees (six of seven analyses with P. fremontii and four of six analyses with P. angustifolia were significant). The above findings indicate that the highest arthropod diversity is achieved in the heterogenous stands of mixed felled and unfelled trees than in stands of cottonwoods, where beavers are not present. These results also indicate that beaver herbivory changes the chemical composition in 10 out of 13 chemical traits in the juvenile growth of two of the three cottonwood species to potentially allow better defense against future beaver herbivory. (4) With P. deltoides, only one of five analyses in chemistry was significant, and none of the four arthropod community analyses were significant, suggesting that this species and its arthropod community responds differently to beaver. Potential reasons for these differences are unknown. Overall, our findings suggest that in addition to their impact on riparian vegetation, other mammals, birds, and aquatic organisms, beavers also may define the arthropod communities of two of three foundation tree species in these riparian ecosystems.

Small rodent communities (Muridae) in Gabonese savannas: species diversity and biogeographical affinities

Mammalia ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Jean-François Mboumba ◽  
Maxime R. Hervé ◽  
Véronique Guyot ◽  
Frederic Ysnel
Keyword(s):  
Ecological Factors ◽  
Abundant Species ◽  
Small Rodent ◽  
Small Rodents ◽  
South West ◽  
New Information ◽  
Different Types ◽  
Mus Minutoides ◽  
Insight Into ◽  
Coastal Basin

Abstract The study contributes to the knowledge of species composition and biogeographical affinities of savannas rodent in Gabon. Unlike small rodents in Gabonese forests, there is little data on the diversity of small rodents in Gabonese savannas. The diversity and distribution of rodent murid communities was studied in four different types of savanna in Gabon: Coastal Basin (South-West), Lopé/Okanda (in the Center), Batéké Plateaux (Southeastern) and Ngougnié/ N’yanga (in the South). A total of 428 individuals representing six species were captured over 11,920 trap nights. Trap success was highly variable (2.2–6.9 %). The most abundant species were Mus minutoides (69%) followed by Lemniscomys striatus (21.5%). Indices of species richness varied from 2 to 5 and diversity (Shannon and Weaver) was low in the four savannas with the highest value at Ngougnié/N’yanga (H′ = 1.2). Species distributions show that Gabonese savanna small rodents conform to four distribution types, with one species known from Zambesian savannas exhibiting austral affinities (Pelomys campanae: occurs in three southern savannas). This new information provides important insight into the biogeography of small rodents at a local and regional level. Moreover, the correspondence analysis highlighted an influence of local ecological factors on population abundance.

scholarly journals Breakfast consumption is positively associated with nutrient adequacy in Canadian children and adolescents

2014 ◽  
Vol 112 (8) ◽  
pp. 1373-1383 ◽  
Author(s):  
Susan I. Barr ◽  
Loretta DiFrancesco ◽  
Victor L. Fulgoni
Keyword(s):  
Children And Adolescents ◽  
Potential Risk ◽  
Nutrient Intake ◽  
Canadian Community Health Survey ◽  
Food Sources ◽  
Nutrient Intakes ◽  
Cross Sectional ◽  
Breakfast Consumption ◽  
Nutrient Adequacy ◽  
The Impact

Although breakfast is associated with more favourable nutrient intake profiles in children, limited data exist on the impact of breakfast on nutrient adequacy and the potential risk of excessive intakes. Accordingly, we assessed differences in nutrient intake and adequacy among breakfast non-consumers, consumers of breakfasts with ready-to-eat cereal (RTEC) and consumers of other types of breakfasts. We used cross-sectional data from 12 281 children and adolescents aged 4–18 years who took part in the nationally representative Canadian Community Health Survey, 2004. Mean nutrient intakes (obtained using a multiple-pass 24 h recall method) were compared among the breakfast groups using covariate-adjusted regression analysis. Usual nutrient intake distributions, generated using the National Cancer Institute method, were used to determine the prevalence of nutrient inadequacy or the potential risk of excessive intakes from food sources alone and from the combination of food plus supplements. Of these Canadian children, 10 % were breakfast non-consumers, 33 % were consumers of RTEC breakfasts and 57 % were consumers of other types of breakfasts. Non-consumption of breakfast increased with age (4–8 years: 2 %; 9–13 years: 9 %; 14–18 years: 18 %). Breakfast consumers had higher covariate-adjusted intakes of energy, many nutrients and fibre, and lower fat intakes. The prevalence of nutrient inadequacy for vitamin D, Ca, Fe and Mg (from food alone or from the combination of food plus supplements) was highest in breakfast non-consumers, intermediate in consumers of other types of breakfasts and lowest in consumers of RTEC breakfast. For vitamin A, P and Zn, breakfast non-consumers had a higher prevalence of nutrient inadequacy than both breakfast groups. The potential risk of excessive nutrient intakes was low in all groups. Efforts to encourage and maintain breakfast consumption in children and adolescents are warranted.

scholarly journals Plant Succession, Ecological Restoration and the Skinks of Stephens Island / Takapourewa

2021 ◽  
Author(s):  
◽  
Cielle Stephens
Keyword(s):  
Ecological Restoration ◽  
Body Condition ◽  
Plant Succession ◽  
Food Sources ◽  
Habitat Types ◽  
Thermal Range ◽  
Tail Loss ◽  
The North ◽  
Occupancy Rates ◽  
The Impact

Ecological restoration often involves revegetation. I have investigated the impact of revegetation on the distribution, abundance and body condition of skinks on Stephens Island (Takapourewa). I tested the prediction that only one, Oligosoma infrapunctatum, of the four skink species (Oligosoma lineoocellatum, O. nigriplantare polychroma, O. infrapunctatum andO. zelandicum) will benefit in terms of abundance and distribution from revegetation. Stephens Island is a Wildlife Sanctuary in the north-western Marlborough Sounds, New Zealand. The island is known for its diverse and abundant reptile community. Prior to the mid 19th century Stephens Island was covered in forest. Nearly 80% of this forest was destroyed following the establishment of a lighthouse and farm on the island in 1894. In 1989, when the control of Stephens Island passed to the Department of Conservation, reforestation became a key conservation goal. Stephens Island is currently a mosaic of different habitat types from pasture to coastal forest. Pitfall traps caught skinks for a mark-recapture study in four replicated habitat types: forest, tussock, pasture and replanted.<br><br>Oligosoma lineoocellatum comprised 75% of all individuals caught. Densities of O. lineoocellatum were higher in replanted habitat (3020/ha in December and 3770/ha in March) than tussock (2690/ha in December and 2560/ha in March) and lowest in the pasture (1740/hain December and 1960/ha in March). Rates of captures were too low to perform density estimates for the other three species. Trap occupancy rates indicate O. nigriplantare polychroma is more common in the tussock habitat, and O. infrapunctatum is more common in the replanted habitat. Few O. zelandicum were found, primarily in the tussock habitat. Pasture areas replanted 13 years ago (now scrub habitat) support a higher diversity and abundance of skinks. Forest areas remain depauperate of skinks. Skink preference for replanted areas suggests that, for now, revegetation benefits their populations, possibly due to greater food sources, lower predation pressure and a wider thermal range.<br><br>Body condition (log weight/ log snout-vent length) and proportion of tail loss of skinks were similar in the different habitat types. However, both O. nigriplantare polychroma and O.lineoocellatum had higher body condition in the replanted than the tussock habitat. Juvenile skinks had significantly lower body condition and a lower proportion of tail loss. Skink body condition was not negatively affected by revegetation or by different habitats, despite the large differences between the habitats. Revegetation currently benefits skink populations. Maintaining a mosaic of habitat types is recommended, because, should revegetation create more forest habitat through plantations or plant succession, it is likely that the population of all four species of skink will decline.<br>

scholarly journals Examining the Key Success Factors for Startups in the Kingdom of Bahrain

2021 ◽  
pp. 9-49
Author(s):  
Muneera Al Sahaf ◽  
Lamea Al Tahoo
Keyword(s):  
Success Factors ◽  
Active Role ◽  
Major Effect ◽  
Fund Raising ◽  
Key Success Factors ◽  
Clear Vision ◽  
Vision 2030 ◽  
The Government ◽  
Oil Wealth ◽  
The Impact

With Bahrain Economic Vision 2030, aspiring the shift from an economy that depends on oil wealth to a diversified economy, including startup businesses.  A number of startups in Bahrain have been growing at a rapid pace in various industries. This is a result of the excellent ecosystem, and support provided to startups by the government in Bahrain. This study aims to examine the key success factors of startups in the Kingdom of Bahrain. The quantitative method was the adopted approach, whereby data was collected to examine the impact of four selected variables; fund-raising, experience, knowledge, and partnerships on the success of startups in Bahrain. The quantitative findings outlined the importance of several factors that were perceived to have a significant influence on the success of Bahraini Startups, where the majority of respondents agreed/strongly that two of the examined factors are considered critical to succeed in startups in the Kingdom of Bahrain. These factors are experience and knowledge, which proved to have an active role to maintain the success of startups. However, the startups’ founders disagreed on the impact of fund-raising and partnerships which are considered to have no major effect on the success of startups. Recommendations of this research include two segments; for founders is to seek more opportunities to enhance their knowledge and capitalize on their experiences, and for government entities to provide and improve training offerings, and facilitate founders’ communication and assist them in reaching out to the investors and the supporting entities, which will provide ease for new startup entry to the market, and establishment of a clear vision with framework prior to embarking the new venture.

Assessing the Contribution of Traditional Foods to Food Security for the Wapekeka First Nation of Canada

2021 ◽  
Author(s):  
Michael A Robidoux ◽  
Derek Winnepetonga ◽  
Sylvia Santosa ◽  
François Haman
Keyword(s):  
Food Security ◽  
Local Food ◽  
Lifestyle Changes ◽  
First Nation ◽  
Food Sources ◽  
Household Food Security ◽  
Traditional Food ◽  
Traditional Foods ◽  
Policy Makers ◽  
The Impact

The food security crisis and disproportionately high burden of dietary related disease amongst northern Indigenous populations in Canada continues to be a troubling reality with little sign of improvement. The Government of Canada is responding by developing programs to support local food initiatives for northern isolated communities. While such investments appear commendable, the impact of local food harvesting to improve food security has yet to be determined. While there are clear nutritional and cultural benefits to traditional food sources, communities face considerable barriers acquiring it in sufficient amounts because of historically imposed lifestyle changes that have increased food insecurity rates. This study responds by providing a novel multidisciplinary approach that draws from firsthand experiences working with First Nations community members in a remote subarctic region in northwestern, Ontario to estimate their community’s total food requirement and the amount of wild animal food sources needed to sustain yearly food intake. This transferrable energy demand approach will be critical for policy makers to put into perspective the amount of wild food needed to have an impact on food security rates and ultimately improve dietary related diseases. Novelty: • It will provide government policy makers information about current harvest yields in a remote northern First Nation to understand the potential contribution of traditional food to improve local food security • Provides Indigenous communities a means to assess local food resources to measure the caloric contributions of traditional foods toward household food security

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