Measuring Productivity – Part II Ecological MethodologyLEC-12 Althoff.

Measuring Productivity – Part II

Ecological Methodology LEC-12 Althoff

Key Definitions

• Productivity = number of offspring (young) produced during a reproductive cycle (season) by a population

• Recruitment = number of young produced in a popn that reach sexual maturity

• Fecundity = rate at which an individual produces offspring (young)

Key Definitions…MAMMALS

• _______________= follicles that erupted, sustained pregnancy, and “remain” in ovary post-partum

• _______________= “sites” on uterine horns were embryos attached

• ________ = near-term development

• ________ = post-partum viable young

Corpora luteum

• Requires sectioning (scapel or razor blade and examination.

• Number per ovary “________” number of fetuses that made it to full term—but not ______ accurate.

Corpora luteum (CL)• Giraffe ovaries

same female, near-term pregnancy

2 – CL 2 “old” CL

Placental scars• Can identify sites where

endometrium/fetus interfaced for exchange of nutrients and waste

• Considered _______ accurate than corpora luteua counts for species with litter sizes >2

• Fetuses not reaching but almostfull-term may leave “equally” pigment scars

• “____” until next breeding cycle at minimum

Fetuses

• Count near-term fetuses

• If not x-ray or ultrasound scan, then must sacrafice adult female

• Not as _____ as newborn count

• Variation in development of young can be observed

Fetuses

Litter – Count Youngpost-partum

• Closer to ___________________ would provide ‘best’ measure of productivity presented so far

Litter – Count Youngpost-partum

_________ _________

• Key considerations (short list): Time of year Time of day

Experience of observers

Weather

Topography/Landscape

Think Spotlight Surveys for White-tailed Deer

1

2

3

4

5

• Key considerations (short list):

Time of year

Ground and Aerial Surveys

1

• Key considerations (short list):

Time of night (including start/stop times)

Ground and Aerial Surveys

2

• Key considerations (short list):

Experience of Observers

Ground and Aerial Surveys

3

• Key considerations (short list):

Weather

Ground and Aerial Surveys

4

• Key considerations (short list):

Topography/Landscape(not vegetation --see 6)

Ground and Aerial Surveys

5

• Key considerations (short list): Other:EquipmentHunting “Pressure”Vegetation

Ground and Aerial Surveys

6

Quivira National Wildlife RefugeKansas 1989-2005

Pre-Rifle Season

Wh

ite-

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d D

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____________________

Quivira National Wildlife RefugeKansas 1989-2005

Pre-Rifle Season

Wh

ite-

taile

d D

eer

____________________