User:Milligancl

Course Instructor, Biology 4931G, 2011/12 | Seminar in Physiology

SAMPLE OF USER PAGE ENTRY
Article to review: Hypoxia (environmental)
(250 word, minimum, critique; how and why to make it better)
There is no real mention of physiological and/or ecological consequences of hypoxia to fish. This is important because aquatic hypoxia is becoming increasingly common in near-shore as well as some off shore areas.
Three key references:
1. Ecological impact of hypoxia on fish ^[1]
- This article mapped out the habitat use by bay anchovy and their key mesoplankton prey and dissolved oxygen levels. The relevant findings are:
  - in the summer months, low oxygen in the bottom layers of the Chesapeake Bay alters the vertical migration of the bay anchovy because bottom
  - as a consequence, fish are limited to the upper, oxygenated layers of the surface waters
  - the mesoplankton prey appear to use the oxygen-poor layers as a refuge, thus potentially limiting access by the bay anchovy
  - this separation of predator and prey may lead to reduction in the bay anchovy population, due to starvation

2. Physiological adaptations in fish routinely encountering hypoxia as part of their life cycle ^[2]
- This is a good review article summarizing the issues associated with life in a hypoxic environment and adaptations shown by intertidal fishes. Some key findings are:
  - metabolism is suppressed at low oxygen levels
  - fishes in low oxygen environments tend to have larger mass-specific gill surface areas, and high-affinity hemoglobin
  - the most hypoxia tolerant species tended to show behavioural adapatations, including aquatic surface respiration and aerial emergence