8095

• UCREFRP Catalog Number: 8095
• Author: National Research Council.
• Title: Impacts of Emerging Agricultural Trends on Fish and Wildlife Habitat.
• USFW Year: 1982.
• USFW - Doc Type: Washington, D.C.
• Copyright Material: NO

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degradation of habitats. Irrigation may result in lower water tables,
and it reduces water in streams and further reduces the amount and
quality of both riparian and upland habitats. The use of agricultural
chemicals and certain mechanical practices to eliminate unwanted
plants will alter the cover and food supply for wildlife.
Rest-rotation grazing, where applicable, can improve wildlife
habitats. Controlled burning to remove brushy species and encourage
grass species will also affect wildlife habitats.

PONDS, LAKES, AND STREAMS

Agricultural practices that alter water flow or increase water runoff
from agricultural land will affect the quantity and quality of pond,
lake, and stream habitats for fish and wildlife. Channelization of
streams to prevent flooding will change the diversity and abundance of
fish and wildlife. Irrigation influences habitats by moving water
from aquifers, ponds, lakes, and streams to agricultural lands.
Agricultural practices that increase soil erosion greatly affect
aquatic habitats by increasing the siltation and by carrying off
nutrients that increase eutrophication. Chemical loading in ponds,
lakes, and streams caused by runoff of agricultural chemicals can
alter the ecological balance by killing certain plants or animals and
thus changing the structure of the habitats. Grazing and cultivation
may damage the riparian zones, reducing these unique wildlife habitats
that are critical to the integrity of streams.

INTERIOR WETLANDS

Interior wetlands are affected by the same factors that influence
ponds, lakes, and streams. In addition, the loss of wetland habitats
through draining and conversion to agricultural uses continues, but
its major remaining impact will be in southern fish and wildlife
habitats, where the majority of new cropland will be developed.

COASTAL WETLANDS AND ESTUARIES

Coastal wetlands and estuaries are influenced by agricultural
practices because they are downstream from farmland. Thus the quality
of habitat in these areas is profoundly affected by runoff of
agricultural chemicals and silt from agricultural lands. Coastal
wetland habitats are indirectly affected by any change in the
allocation of acreage to cropland or pasture. Estuarine areas are the
nurseries for most of the coastal and Gulf fish stocks. Increased
agricultural use of the estuarine habitats may affect bay, river
mouth, and shallow coastal areas. At the present time, the water
quality of estuaries is subject to regulation by the government. The
estuaries are fertilized by land runoff, but, at the same time,
harmful chemicals are being transported and deposited. A proper

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