The Annual Cycles of Activity and Weight of Rock Squirrels (Spermophilus variegatus) in Southeastern Arizona

1991 ◽  
Vol 126 (1) ◽  
pp. 159 ◽  
Author(s):  
Joseph Charles Ortega
Keyword(s):  
Annual Cycles ◽  
Spermophilus Variegatus

The ecological state of the Elefsis Bay prior to the operation of the athens sea outfall

1994 ◽  
Vol 30 (10) ◽  
pp. 161-171 ◽  
Author(s):  
A. J. Theodorou
Keyword(s):  
River Discharge ◽  
Thermal Stratification ◽  
Lower Layer ◽  
Ecological State ◽  
Annual Cycles ◽  
Untreated Wastewater ◽  
Resistant Species ◽  
Acartia Clausi ◽  
Gyrodinium Aureolum ◽  
Agricultural Areas

Nutrient pollution in Elefsis Bay arises mainly from the disposal of Athens untreated wastewater at the eastern entrance of the Bay. The absence of river discharge, lack of cultivated agricultural areas providing runoff and the Bay's limited circulation provide the conditions for the Bay's eutrophication by the discharge of untreated wastewater. In the spring of 1993 this discharge was replaced by a new deep outfall system. To monitor any future changes an assessment of the present ecological state of the Bay is required. Analysis of appropriate data showed that Elefsis Bay accumulates nutrients. In summer a strong thermal stratification causes anoxic conditions to occur in the lower layer. The ecosystem exhibits reduced species diversity and strong oscillations of plankton annual cycles. Flagellates (Cryptomonas sp.) dominate the phytoplankton, followed by dinoflagellates (Gyrodinium aureolum, Prorocentum dentatum) and only in the spring diatoms (Nitzschia) predominate. The zooplankton was dominated by copepods (Acartia clausi) and cladoceran (Podon polyphemoides). Macrobenthos consists of a small number of pollution-resistant species of Polychaeta (Capitela capitata), whilst in summer only one species of Molluscs (Corbula gibba) survives.

scholarly journals Potential of Small Culverts as Wildlife Passages on Forest Roads

2021 ◽  
Vol 13 (13) ◽  
pp. 7224
Author(s):  
Hsiang-Ling Chen ◽  
Erin E. Posthumus ◽  
John L. Koprowski
Keyword(s):  
Animal Movement ◽  
Small Dimension ◽  
Lynx Rufus ◽  
Tamiasciurus Hudsonicus ◽  
Red Squirrels ◽  
Forest Roads ◽  
Alternative Pathways ◽  
Slow Moving ◽  
Trail Cameras ◽  
Spermophilus Variegatus

Roads and traffic can cause animal mortality. Specifically, roads serve as barriers by impeding animal movement, resulting in demographic and genetic consequences. Drainage structures, such as culverts, can provide linkages between habitat patches. However, the potential of small culverts with diameters of <60 cm (e.g., wildlife passages that facilitate movement on forest roads) are relatively unknown. In this study, we used trail cameras to monitor the use of 14 small culverts, by mammals, along forest roads on Mt. Graham, home of the critically endangered Mt. Graham red squirrels (Tamiasciurus hudsonicus grahamensis), in southeastern Arizona, USA. From 2011 to 2013, we only recorded 20 completed road crossings through culverts. More than half of culvert uses were by striped skunks (Mephitis mephitis), followed by the rock squirrel (Spermophilus variegatus) and the bobcat (Lynx rufus). The Mt. Graham red squirrel was the only species that was common along the roads, but never crossed the roads. Culverts with higher usages were characterized by shorter culvert lengths and absence of accumulated soil inside the culverts. Our study shows that small-dimension drainage systems may provide alternative pathways for wildlife crossing roads, especially for slow moving and ground dwelling species. However, the potential of small culverts assisting wildlife crossings can only be maximized when culverts are accessible year-round.

Modelling annual cycles of primary production in different regions of the Bohai Sea

1998 ◽  
Vol 7 (3‐4) ◽  
pp. 258-264 ◽  
Author(s):  
HUIWANG GAO ◽  
SHIZUO FENG ◽  
YUPING GUAN
Keyword(s):  
Primary Production ◽  
Bohai Sea ◽  
Annual Cycles ◽  
The Bohai Sea

Annual cycles of body weight in the Namie's frosted bat, Vespertilio superans superans

2009 ◽  
Vol 196 (3) ◽  
pp. 417-430 ◽  
Author(s):  
Kimitake Funakoshi ◽  
Teru Aki Uchida
Keyword(s):  
Body Weight ◽  
Annual Cycles

Reproduction during Two Annual Cycles in a Population of Peromyscus leucopus noveboracensis

1976 ◽  
Vol 57 (3) ◽  
pp. 593-595 ◽  
Author(s):  
D. L. Rintamaa ◽  
P. A. Mazur ◽  
S. H. Vessey
Keyword(s):  
Peromyscus Leucopus ◽  
Annual Cycles

Annual Cycles of the Kidney Fat Index in a Southeastern White-Tailed Deer Herd

1984 ◽  
Vol 48 (3) ◽  
pp. 969 ◽  
Author(s):  
Paul E. Johns ◽  
Michael H. Smith ◽  
Ronald K. Chesser
Keyword(s):  
Annual Cycles ◽  
Kidney Fat ◽  
Kidney Fat Index

scholarly journals Spatially different annual cycles but similar haemosporidian infections in distant populations of collared sand martins

BMC Zoology ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Steffen Hahn ◽  
Martins Briedis ◽  
Christos Barboutis ◽  
Raffaella Schmid ◽  
Martin Schulze ◽  
...  
Keyword(s):  
West Africa ◽  
Chronic Infection ◽  
Blood Parasite ◽  
Spring Migration ◽  
Lake Chad ◽  
Annual Cycles ◽  
Nonbreeding Season ◽  
Breeding Populations ◽  
High Parasitaemia ◽  
Western Palaearctic

Abstract Background Populations of long-distance migratory birds experience different environments and are consequently exposed to different parasites throughout their annual cycles. Though, specific whereabouts and accompanied host-parasite interactions remain unknown for most migratory passerines. Collared sand martins (Riparia riparia) breeding in the western Palaearctic spend the nonbreeding period in Africa, but it is not yet clear whether specific populations differ in overwintering locations and whether these also result in varying infections with vector-transmitted endoparasites. Results Geolocator tracking revealed that collared sand martins from northern-central and central-eastern Europe migrate to distant nonbreeding sites in West Africa and the Lake Chad basin in central Africa, respectively. While the ranges of these populations were clearly separated throughout the year, they consistently spent up to 60% of the annual cycle in Africa. Ambient light recorded by geolocators further indicated unsheltered roosting during the nonbreeding season in Africa compared to the breeding season in Europe. We found 5–26% prevalence of haemosporidian parasites in three breeding populations and one migratory passage population that was only sampled but not tracked. In total, we identified seven Plasmodium and nine Haemoproteus lineages (incl. two and seven new lineages, respectively), the latter presumably typical for swallows (Hirundinae) hosts. 99.5% of infections had a low intensity, typical for chronic infection stages, whereas three individuals (0.5%) showed high parasitaemia typical for acute infections during spring migration and breeding. Conclusions Our study shows that blood parasite infections are common in several western Palaearctic breeding populations of collared sand martins who spent the nonbreeding season in West Africa and the lake Chad region. Due to long residency at the nonbreeding grounds blood parasite transmissions may mainly occur at host population-specific residences sites in Europe and Africa; the latter being likely facilitated by unsheltered roosting and thus high vulnerability to hematophagous insects. The rare cases of high parasitaemia during spring migration and breeding further indicates either relapses of chronic infection or primary infections which occurred shortly before migration and during breeding.

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