Fish Species Richness in Relation to Lake Area, pH, and Other Abiotic Factors in Ontario Lakes

Abstract

Survey data from 2931 Ontario lakes were analyzed to determine how fish species richness was empirically related to a set of 19 physical and chemical limnological variables. Lake area was the dominant factor, explaining 18% of the variation in species number. Total aluminum, latitude, dissolved organic carbon, and elevation together explained an additional 16%. The strong relationship between species number and lake area was quantified using lakes with pH [Formula: see text] and then applied to ail the surveyed lakes to estimate species number. Deviations from the expected values indicated that species number decreased with decreasing pH below 6.0, resulting in significantly fewer species in lakes with pH < 6.0. In the subset of lakes with pH < 6.0, pH alone explained 21% of the variation in species number; elevation, lake area, and dissolved organic carbon together explained an additional 20%. Interactions between pH and lake area were identified; lake size decreased significantly both at low pH (<6.8) and at high pH [Formula: see text]. An understanding of these interactions was essential in explaining the relative roles of pH and lake area in determining species richness.

Can settlement in natal-like habitat explain maladaptive habitat selection?

“…While the relative size of a potential breeding lake to its natal one might be determined by quick visual inspection, acidity seems more difficult to assess, owing to a shortage of taste receptors and insensitivity to acidity in birds [39]. Perhaps loons detect not pH per se, but a correlate such as diversity of piscine and/or invertebrate prey [40]. Most studies of habitat selection focus on its potential to promote reproduction, not survival [13], but NHPI seems likely to promote the latter.…”

Common Loon Reproductive Success in Canada: the West is Best but Not for Long

“…5). This result may partially explain why breeding Common Loons prefer to settle on larger compared to smaller lakes (e.g., Kuhn et al 2011) because larger lakes often have higher pHs and more food than smaller lakes (e.g., Rago and Wiener 1986, Matuszek and Beggs 1988, McNicol et al 1995.…”

“…By virtue of their volume, smaller lakes also have lower total numbers of fish than larger lakes (Alvo et al 1988, Piper et al 2012. Moreover, some smaller lakes receive relatively larger inputs from acid precipitation and hold fewer substances that neutralize acids compared to larger lakes (Eilers et al 1983), which means that smaller lakes generally have lower pH than larger lakes (e.g., Rago and Wiener 1986, Matuszek and Beggs 1988, McNicol et al 1995. Thus, smaller lakes typically are warmer and have lower pH than larger lakes, which likely explains why methylmercury is more abundant in smaller lakes (Bodaly et al 1993, Jeremiason et al 2006.…”

Perspectives on the use of lakes and ponds as model systems for macroecological research

“…On the other hand, despite some general environmental influences, lake characteristics (such as area, age, temperature or productivity) are not necessarily correlated, or at least are not as spatially autocorrelated as the characteristics of terrestrial landscapes. These characteristics make direct hypothesis testing easier in lentic habitats, even though several factors can interact to affect diversity gradients in a non-linear way (see Matuszek and Beggs, 1988).…”