Digital Journal Element 2

Class Learning

Moist Soil Management 

What is Moist Soil Management?

Moist soil management is a land management practice that provides wintering and migrating waterfowl with critical additions to their diet (Strader and Stinson 2005). This practice was designed to help increase the foraging ability of waterfowl on agricultural lands while they are not being used for crops. It is a management plan that has been implemented on many refuges and private lands on both the pacific and central flyways in North America. It is heavily practiced near the Mississippi river and the California Central Valley (Strader and Stinson 2005).

Why is it necessary?

Wetland habitat is a habitat type that is seeing major losses because wetlands normally possess fertile soil, which is a valuable resource for agriculture. This has led to massive wetland habitat conversions to agricultural lands. Many states have seen total net losses of over fifty percent with some totally losses in the low ninety percent. This has eliminated many stop over and wintering sites utilized by waterfowl during their migratory life cycles. Waterfowl cannot complete their yearly migrations with a flyway fragmented by areas suitable for them to eat and gain the reserves required to complete their life cycle. Moist soil management prevents fragmentation of flyways by managing agricultural lands in a way that still provides waterfowl with stopover and wintering habitat.

How are the agricultural lands managed?

Croplands are planted with desired crops between March and July, depending upon the needed time of germination. The agricultural plants are grown until August to mid-October and, then are harvested. The pasture is then gradually flooded from August, when waterfowl migrate to their wintering grounds. During late December and January the flooding is completed and maintained to provide wetland habitat for the wintering waterfowl. At the end of January, the water level is slowly drawn down to allow the land to be used for crops the following season.

What factors are involved?

There is no easy formula for success across the for moist soil mangement beyond the need to develop a plan; frequently monitor plant and wildlife responses; and keep detailed records of natural conditions, management actions, and plant and wildlife responses (Strader and Stinson 2005). Many factors must be considered at every stage of this management plan to insure it’s success. The six most important factors are:

11)      Sunlight reaching plants

22)      Soil temperature

33)      Soil moisture

44)      Soil chemistry

55)      Seed bank

66)      Successional stage of plant community

1) Moist soil managed plants require full sun exposure. This normally implies an early successional community with short vegetation and no trees.

2) The temperature of the soil at the time of draw down determines the composition of the seeds that germinate from the seed bank. Draw down should be timed with the preferred germination time of desired plants.

3) Soil moisture must be maintained to encourage the growth of the desired wetland plants. Moisture is a factor that should be continuously monitored and maintained throughout this process

4) Soil should be maintained at the right pH and nutrient levels preferred by desired plants. Salinity is a factor that must be managed for in coastal agricultural areas and, can be used as an herbicide against undesired salt-intolerant plants.

5) Seed bank must maintain the presence of desired annual plants

6) Waterfowl capitalize on annual, early successional plants. To maintain this successional stage, managed lands must be rotated every 2 to 4 years. This can be maintained by following a 2 to 4 year rotational plan for your croplands.
(Strader and Stinson 2005)

What plants are desired?

Desired plants are annual plants that produce a large amount of seeds.

Digitaria spp.                         Crab grass

Echinochola spp.         Millet, etc

Eleocharis spp.           Spikerush

Eragrostis spp.            Love grass

Lemna spp.                 Duckweed

Najas spp.                  Naiads

Oryza sativa                Red rice

Polygonum spp.          Ladysthumb, etc.

Potamogeton spp.       Pondweed, etc.

Sagittaria spp.             Duck potato, etc.

Scirpus spp.                Bulrush, etc.

Zizania aquatic            wildrice

(Strader and Stinson 2005)

Seed Dispersal (Lowery and Langle 2013)

Waterfowl have the ability to disperse seeds from their feeding sites both internally and externally.  

There are three different factors involved in seed dispersal including

Seed size

Seed retention time in the gut

Seed dispersal distance

It is important that the seeds have a low retention time to increase the chances of germination.

Triumph Ceremonies 

There are many different aspects of the triumph ceremony behavior observed within the Canada goose and many other species that exhibit pair bonding. There are many aspects of the ceremony and its purpose in the mating process. The ceremony has been divided  into cackling and rolling parts and mapped out every aspect of the ceremony its self. These ceremonies are “closely associated” with attacks from rival couples or individual. These attacks were normally caused by males in response to male threat on a female mate or territory.

Social Allies

It has been claimed that the presence of a social ally “may reduce stress, increase success in agonistic encounters and ease of access to resources in waterfowl.”  It has been shown that small social groups were met with more stress than larger social groups. This occurred for a number of reasons but, lack of necessary support was the main underlying theme. This is important to managers because to set bag limits they  must know what an ideal flock size is. If the flock size is reduced to the point where it stresses the birds it may be bad for their reproduction.

 DNA and species monitoring

Traditional population monitoring is slowly being phased out and replaced by genetic analysis. From genetics we can determine things like animal origin, population dynamics, and even historical species status and range. A new technique is also being developed where you can use environmental samples, (like water or mud) to test for animal presence and absence using mitochondrial DNA left by the animal in the environment. The water is spun down in a centrifuge and a polymerase chain reaction performed on the sample, using species specific primers. If the species is present the DNA will amplify and appear on an electrophoresis gel.  This technique is being expanded to include a census number using quatative PCR.

 

 Lowery, M. and Langle, P. 2013. Waterfowl Seed Dispersal

Scheiber, Isabella B.R., Brigitte M. Weib, Didone Figerio, and Kurt Kotrschal. 2005 Active and passive social support in families of graylag geese (Anser anser). Konrad Lorenz Forschungsstelle fur Ethologi.A-4645:11.

Radesater, T. 1975. Interactions between male and females during the Triumph Ceramony in the Canada Goose ( Branta Canadensis L.). Tierpsychol., 39:189-205