The influence of external cation concentration on the hatching of amphibian embryos in water of low pH

1985 ◽  
Vol 63 (11) ◽  
pp. 2649-2656 ◽  
Author(s):  
Joseph Freda ◽  
William A. Dunson
Keyword(s):  
Rana Sylvatica ◽  
Low Ph ◽  
Early Mortality ◽  
Ambystoma Maculatum ◽  
Perivitelline Space ◽  
Acidic Water ◽  
Cation Concentration ◽  
Amphibian Embryos ◽  
Ambystoma Jeffersonianum

Amphibian embryos exposed to water of low pH were killed by two distinct mechanisms. At very low pH levels, embryos stopped development soon after exposure to test solutions. At higher but still lethal pH levels, embryos became curled within a shrunken perivitelline space and failed to hatch (curling defect). The addition of Ca, Mg, and to a lesser extent Na (> 10 mg/L), prevented the early mortality of embryos in acidic water. However, increasing concentrations of these ions also caused the curling defect. Embryos of Ambystoma maculatum and Ambystoma jeffersonianum were generally able to hatch even though they became curled, but Rana sylvatica remained trapped and died. Consequently, as the concentration of Ca, Mg, or Na was increased at low pH, greater numbers of embryos of A. maculatum and A. jeffersonianum hatched, while survival of embryos of R. sylvatica was drastically reduced.

Toxicity of Amphibian Breeding Ponds in the Sudbury Region

1993 ◽  
Vol 50 (7) ◽  
pp. 1497-1503 ◽  
Author(s):  
Joseph Freda ◽  
D. Gordon McDonald
Keyword(s):  
Organic Compounds ◽  
Rana Sylvatica ◽  
Low Ph ◽  
Ambystoma Maculatum ◽  
Bufo Americanus ◽  
Spotted Salamander ◽  
Water Ph ◽  
Dissolved Organic Compounds ◽  
High Concentrations ◽  
Toad Bufo

We measured the survival of transplanted embryos and tadpoles of the wood frog (Rana sylvatica), the American toad (Bufo americanus), and the spotted salamander (Ambystoma maculatum) in 16 ponds located approximately 60 km south of Sudbury, Ontario. Mortality of embryos of all species and mortality of B. americanus tadpoles were correlated only with water pH. In two low-pH ponds, high concentrations of dissolved organic compounds might have been a toxic component. Aluminum and pH were correlated with mortality for only R. sylvatica tadpoles. Overall, Al did not appear to be very toxic in both laboratory and field exposures possibly due to complexation by dissolved organic compounds.

Effects of pH on the early development and growth and otolith microstructure of chinook salmon, Oncorhynchus tshawytscha

1985 ◽  
Vol 63 (1) ◽  
pp. 22-27 ◽  
Author(s):  
G. H. Geen ◽  
J. D. Neilson ◽  
M. Bradford
Keyword(s):  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Growth Increment ◽  
Low Ph ◽  
Acidic Water ◽  
Daily Growth ◽  
Stage Of Development ◽  
Growth Increments ◽  
Effects Of Ph ◽  
Daily Growth Increment

Chinook salmon (Oncorhynchus tshawytscha) eggs, alevins, and fry were reared in pH 4.5, 5.0. 5.5, 6.2 (control), and 7.0 water from the eyed stage of development. Survival through hatching was >90% in all instances. Alevin mortality was high at pH 4.5 and 5.0. Fry were more tolerant of low pH than alevins. Growth rates of alevins and fry held at or above pH 5.0 and 4.5, respectively, were not affected by pH, nor did exposure to acidic water retard otolith development or result in their resorption. One otolith daily growth increment was formed every 24 h in alevins and fry irrespective of pH. Widths of otolith daily growth increments decreased when fry were transferred to pH 4.5 water and increased on their return to higher pH indicating changes in growth rate. Transfer of fry from pH 6.2 to pH 5.0 or 5.5 had no effect on increment widths.

scholarly journals OXYGEN TRANSPORT IN EGG MASSES OF THE AMPHIBIANS RANA SYLVATICA AND AMBYSTOMA MACULATUM: CONVECTION, DIFFUSION AND OXYGEN PRODUCTION BY ALGAE

1994 ◽  
Vol 197 (1) ◽  
pp. 17-30
Author(s):  
A Pinder ◽  
S Friet
Keyword(s):  
Oxygen Delivery ◽  
Developmental Stages ◽  
Rana Sylvatica ◽  
Water Channels ◽  
Ambystoma Maculatum ◽  
Egg Mass ◽  
Oxygen Production ◽  
Mass Model ◽  
Egg Masses ◽  
Algal Symbiont

Many amphibians lay their eggs in gelatinous masses up to 10­20 cm in diameter, posing problems for diffusive oxygen delivery. Oxygen may also be provided by water convection between eggs or by oxygen production by endogenous algae. We studied egg masses of two local amphibians, Rana sylvatica and Ambystoma maculatum, to estimate the importance of each of these processes. We injected dye to check for water channels, measured oxygen partial pressures within egg masses to determine the influence of external water convection and lighting, measured oxygen consumption and production in darkness and light and calculated expected gradients through egg masses with a cylindrical, homogeneous egg mass model. Rana sylvatica had relatively loose egg masses with water channels between the eggs; water convection was important for oxygen delivery. Ambystoma maculatum had firm egg masses with no spaces in the jelly between eggs; thus, there was no opportunity for convective oxygen delivery. The egg masses were cohabited by Oophila ambystomatis, a green alga found specifically in association with amphibian egg masses. Oxygen delivery in A. maculatum was by diffusion and by local production by the algal symbiont. Analysis of a cylindrical egg mass model and measurement of oxygen gradients through egg masses indicated that diffusion alone was not adequate to deliver sufficient O2 to the innermost embryos at late developmental stages. In the light, however, egg masses had a net oxygen production and became hyperoxic. Over the course of a day with a 14 h:10 h light:dark cycle, the innermost embryos were alternately exposed to hyperoxia and near anoxia.

Treatment of acidic water from Bekok River using open limestone channel

2007 ◽  
Vol 7 (4) ◽  
pp. 65-71 ◽  
Author(s):  
A. Aris ◽  
N. Mokhtar ◽  
R. Muslim ◽  
Z. Ujang ◽  
Z. A-Majid
Keyword(s):  
Contact Time ◽  
Soil Characteristics ◽  
Low Ph ◽  
Agricultural Activities ◽  
Raw Water ◽  
Acidic Water ◽  
Initial Ph ◽  
Industrial Use ◽  
The Cost

Bekok River is one of the raw water resources for Batu Pahat treatment plants which supply treated water for domestic, institutional, commercial and industrial use. Due to soil characteristics and agricultural activities in the catchment area, pH of lower than 5.5 is common to the river, particularly in the stretch where the water intake point is located. However, at times, Bekok River registered low pH of less than 3.5 and hence caused problems to the treatment plants. The cost to neutralise the water increased and treatment scheduling became more complicated. A preliminary laboratory scale study has been conducted to determine the viability of using an open limestone channel as an in-situ pH treatment in the river. Two sets of experiments using synthetic and actual raw waters with various sizes and amount of limestone were carried out. Results indicate the viability of the process. Depending on the initial pH and acidity of the raw water, the pH can rise to 6.0 within 30 minutes of contact time. The amount and size of limestone was found to play an important role in minimising the contact time.

Trypanosoma ambystomae in Ambystoma spp. (order Caudata) in southern Ontario

1980 ◽  
Vol 58 (3) ◽  
pp. 466-469
Author(s):  
Patrick T. K. Woo ◽  
James P. Bogart ◽  
David L. Servage
Keyword(s):  
North America ◽  
Host Range ◽  
Ambystoma Maculatum ◽  
Western North America ◽  
Southern Ontario ◽  
First Report ◽  
Ambystoma Jeffersonianum ◽  
Ambystoma Laterale ◽  
Division Process

Using the haematocrit centrifuge technique, Trypanosoma ambystomae was recorded from Ambystoma jeffersonianum, Ambystoma platineum, Ambystoma laterale, Ambystoma maculatum, and Ambystoma tremblayi from five areas in southern Ontario. The percentage of infected animals varied from about 5% in A. tremblayi to 27% in A. platineum and A. maculatum. This report not only expands the host range for the trypanosome, it is also the first report of it being found outside western North America. The division process of the trypanosome in the salamander is described and it is shown that it can be maintained in salamanders in the laboratory by blood inoculation.

Intraspecific variation in Hydrogen Ion and Aluminum Toxicity in Bufo americanus and Ambystoma maculatum

1987 ◽  
Vol 44 (9) ◽  
pp. 1622-1628 ◽  
Author(s):  
Karen L. Clark ◽  
Bruce D. LaZerte
Keyword(s):  
Significant Variation ◽  
Hatching Success ◽  
Aluminum Toxicity ◽  
Natural Populations ◽  
Acid Tolerance ◽  
Ambystoma Maculatum ◽  
Hydrogen Ion ◽  
Perivitelline Space ◽  
Laboratory Studies ◽  
Bufo Americanus

Variation in hydrogen ion and aluminum toxicity was measured among clutches in one Bufo americanus population from a pond with pH 5.96 and both among clutches and ponds in four Ambystoma maculatum populations from ponds with pH levels from 4.44 to 6.19. There was significant variation among clutches, but in general, B. americanus hatching success was reduced at pH 4.1 compared with pH6.0. At pH 4.1,200 μg Al/L caused even greater embryonic mortality. Aluminum toxicity did not vary among clutches; however, variation in acid tolerance was such that clutches with the highest hatching success at pH 6.0 had the lowest hatching success at pH 4.1. Hatching success of A. maculatum also varied among clutches, but in general, hatching success was lower at pH 4.3 than at pH 6.0, and 200 μg Al/L at pH 4.3 increased hatching success compared with when no aluminum was present. Variation in acid tolerance among pond populations was so large that one population had higher hatching success at pH 4.3 than at pH 6.0. Ambystoma maculatum hatching success was not related to diameter of the perivitelline space just prior to hatch. The wide variation in acid tolerance among clutches of B. americanus and among populations of A. maculatum suggests that laboratory studies using small numbers of clutches may not adequately represent the response of the natural populations.

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