Drought

Environmental warming due to climate change is closely associated with increased rainfall from extreme storms as well as periods of reduced rainfall and drought. As precipitation becomes less frequent and more intense, longer time periods between rain events create drought conditions. Future fall and winter months will likely see the largest increase in precipitation, with winter snows increasingly replaced by rain and ice. Earlier spring arrivals will melt accumulated snows sooner, causing evaporation and dry conditions for late spring through fall. Periods of drought-like conditions followed by intense rain events cause runoff and erosion, and the soil is unable to absorb the extra moisture, which is needed to support plant and animal life.

How Drought Is Affecting Wildlife

Aquatic species are most significantly impacted by drought conditions, but all wildlife are affected by insufficient water for drinking. Droughts occurring during the spring and summer months lead to reduced volume in rivers and warmer water because of the shallower depths. These conditions directly threaten coldwater fish species such as brook trout and slimy sculpin. Reduced river volume also affects the depth and water temperatures of the ponds, lakes, and wetlands they flow into. Some fish that thrive in deeper water may adapt, but they may also face new competition from species that are better suited for warmer, shallower water.

Rainfall is essential for healthy habitat for all wildlife, and droughts create conditions that stress forests and increase the risk of wildfires. The pressure of drought and increased temperatures during the summer provide opportunity for the advancement of invasive species such as the hemlock woolly adelgid, which feeds on hemlock trees. As tracts of hemlock are lost to infestation, young trees are much slower to grow due to reduced seedling success in dry conditions. Many native species rely on hemlock stands for cover year round, but this type of woodland is critical to deer populations because it comprises deer wintering areas where deer congregate during snowy months. Drought will also allow gypsy moths to proliferate, which will adversely affect oak trees and acorn production, a significant mast crop important to bears, turkeys and other wildlife.

What NH Fish and Game Is Doing in Response to Drought

Climate change is always a consideration at the New Hampshire Fish and Game Department regarding the management of native wildlife. The Department has worked to remove old dams and increase culvert sizes to help ensure that water flow is not blocked. This is important to fish and other aquatic species, but significant when considering that fish reliant on cold water temperatures may need to move upstream during the dryer, hotter summer months associated with advancing climate change to reach cooler water. The ability to move freely and without obstruction benefits both coldwater and warmwater fish as they respond to warming and diminished waters during drought.

Biologists routinely monitor many fish populations, as well as game and nongame species. While deer populations are surveyed during the deer-hunting season at check stations, deer yards are also surveyed during the winter to further determine the health of the herd, which may be affected by drought.

As wildlife responds to the pressures of drought, their patterns of travel will change as they look for water sources. Wildlife corridor recommendations, habitats provided by the Department’s Wildlife Management Areas, and partner conservation easements provide thousands of acres in support of wildlife movement and habitat preservation.

Drought and People

Drought conditions create soils less able to absorb water in severe rain storms. This contributes to extreme flooding and erosion which threaten aquatic life in rivers. Drought stresses all forest habitats, making woodlands more susceptible to invasive insects and plants as well as wildfires. As cover thins in some areas, wildlife will move to more protective habitat, which would affect backyard wildlife viewing and the ranges of game species such as deer. Drought increases the potential for reduced or failed mast crops, such as berries and acorns, on which many wildlife species rely for food. With these resources reduced, increased interactions between people and wildlife may increase as animals such as bears look for alternatives to their natural foods.

Taking Action

• Replace asphalt with naturally draining surfaces so rainwater is absorbed into the ground.
• Plant trees and other plants in your yard—they absorb water to help other plant and animals survive drought conditions and help cool your yard during warmer conditions.
• Volunteer to be part of your community’s conservation commission.
• Educate yourself and share your understanding with friends and family about how climate change affects wildlife and habitats. 
• Start planning now for good ecological health and get involved in your local community by addressing potential climate change issues in your town or region. 
• Support and volunteer for environmental and conservation organizations that address climate change impacts to wildlife and habitats.
• Become a citizen scientist and help collect data on plants, wildlife, water, and weather.