W ILDLIFE T ECHNICAL S ERVICES, I NC.

Transcription

1 W ILDLIFE T ECHNICAL S ERVICES, I NC. Memorandum To: From: Subject: Mr. Derrick Gibbs, Reunion Homeowner Association Lake Management Committee W. H. Tomlinson, President, Wildlife Technical Services, Inc. Reunion Fisheries Management with attachments re: Power Point presentation, artificial structure location, photographs of artificial structure placement and creel limits/other recommendations Date: May 6, 2009 In response to an April 1, 2009 survey of the Reunion Lakes and associated fishery and as requested at our subsequent meeting with you at the Reunion Grill on April 23, I am providing related information, recommendations and attachments pertinent to our findings. As discussed at our meeting and in subsequent telephone conversations, Wildlife Technical Services has been an active participant in the Reunion development process for a number of years. Our primary point-of-contact has been with the Mr. Keith Kent, Vice- President, Reunion, Inc. Wildlife Technical Services, Inc. has been involved in the natural resources management business for 20 years; finding a common bond between terrestrial and aquatic resources and the property owners called to be stewards of those resources. Our company has, since 2003, provided lake management and fisheries management services to the Reunion Development on an as called/as needed basis. Primary management emphasis has been on stocking and subsequent maintenance of a viable fishery at Reunion. Fish sampling and associated written reports were, until 2008, conducted/contributed on a quarterly basis. Beginning in 2008, we were asked to reduce our Quarterly sampling efforts to an annual sampling in April/May of successive years. The Power Point presentation included herein, details general and specific information relative to the current status of Reunion Lake (North Lake) and South Lake. It additionally gives a brief historical perspective of the area lakes since Please advise if you have questions or if you have difficulty opening or disseminating the information to other Reunion homeowners. P.O. BOX , VICKSBURG, MISSISSIPPI / / (FAX)

2 Also included in this transmittal, is a listing of 49 underwater fish structures, complete with GPS coordinates, which were placed in Reunion Lake in Water depth at the time of placement is also included, as is information as to the number and orientation of the structure, e.g. vertical or horizontal placement. For safety purposes, the structures were all placed well outside of the ski area. Pictures of the structures are being provided as visual reinforcement. Lack of underwater structure is, perhaps, the greatest immediate challenge for development of the Reunion fishery; particularly with reference to South Lake. The piers and retainer walls provide significant structure in Reunion Lake and our fish sampling efforts were extremely productive in those areas. Underwater structure attracts forage fish because it affords escape cover from predatory bass and crappie. Nevertheless, they all crowd around structure because it represents an element of food and cover for all. A lack of underwater cover in South Lake results in a more stratified and dispersed population, making the sampling effort more difficult and less productive. Collecting discarded Christmas Trees in December/January and sinking those trees appropriately in the respective lakes is a low cost/high return project that is environmentally sensitive and incredibly effective for building underwater fish habitat. Other types of structure can be built or purchased commercially albeit at considerably more expense. Recognizing that there is an interest by some homeowners in adding chemical fertilizers to the lakes, let me suggest that such practice be held in abeyance until there is a bit more stability in the adjacent watersheds. The lakes currently have a significant, though not excessive, plankton bloom, which is a foundational microscopic vegetative element of freshwater fish production. Conversely, the lakes may also become somewhat turbid with suspended sediment arising from lake bank erosion, adjacent development activities, and upstream/off property run-off events. Both plankton blooms and turbidly limit sunlight penetration, which is beneficial to perpetuation of lake integrity by inhibiting the growth of noxious underwater plants. Unfortunately, turbidity issues have more short and long term negative impacts than positive ones and can compromise the integrity and longevity of a plankton bloom. Much of Reunion Lake already benefits from nutrient runoff from adjacent yards, which are fertilized for turf, flower and other cultivated crops associated with homeownership. Since plankton is a microscopic plant, it, like most plants, responds favorably to artificial fertilization. Plankton produces oxygen in the presence of sunlight; and that can provide positive benefits. Nevertheless, adding chemical fertilizers directly to the lake(s) can also lead to an excessive bloom event, particularly following an extreme rain event during which copious amounts of runoff from fertilized properties end up in adjacent lakes. Heavy plankton blooms subjected to several consecutive cloudy days and increased turbidity often begin to die from lack of sunlight. As the bloom begins to die, the decomposition process begins to consume oxygen, resulting in hypoxia or oxygen depletion similar to, but on a much smaller scale than, that which is occurring in the Hypoxic or Dead Zone in the Coastal United States. As the oxygen is depleted, significant concentrations of fish may also be affected, the cumulative result which can be catastrophic for the fish population and unbearable for adjacent homeowners. In consideration of the strongly negative effects which can occur from excessive bloom events and in consideration of the current visual depth and P.O. BOX , VICKSBURG, MISSISSIPPI / / (FAX) PAGE 2 OF 4

3 water chemistry, it is my recommendation that additional chemical fertilizer not be added to Reunion lakes at this particular point-in-time. Please keep in mind that we, like others in the resource management business, have access to and in fact sell copious amounts of aquatic fertilizer. We do not, however, feel that such an application of product or expenditure of funds are needed at this particular juncture. In addressing another specific question regarding creel limits for bass, please be advised that these and other recommendations are detailed in the Power Point presentation attached. Our bass specific recommendations are as follows and are based upon valid fish samples and consideration of the size, age and stocking of the related impoundments: Reunion Lake o Remove bass 13 and smaller. o Limit removal of bass to 5 fish per angler per day. o Release all bass 20 and greater. Trophy bass can be replicated by a knowledgeable taxidermist using length and girth measurements. A photo of the fish is also helpful. South Lake Catch and release all bass Based upon our sampling effort in both Reunion Lake and South Lake, unlimited removal of the following size classes will result in the following population depletion rates: 13 inches and less 37% 14 inches and less 56% 15 inches and less 71% 16 inches and less 81% 17 inches and less 89% 18 inches and less 92% 19 inches and less 97% As you can see, unlimited harvest of 15 inch and smaller fish would deplete the current bass stocking to an unacceptable level, thereby opening up the food chain to be occupied by other predator species; namely crappie and catfish. Overpopulation by predominant forage species, such as shad and bluegill, could also be problematic. Finally, comparisons were made at our meeting on April 23 between Reunion Lakes management and the management of Lake Caroline. Such comparisons are not at all pertinent to Reunion, since size, connectivity and longevity are vastly different. Lake Caroline encompasses approximately 835 contiguous acres and is approximately 20 years old. Conversely, Reunion Lakes are comprised of two impoundments of different ages; the oldest of which is 6 years and the youngest of which is 3 years. They are connected by a narrow channel which is bridged. Each is approximately 200 acres. Comparing Reunion to Caroline is paramount to comparing an adolescent to an adult. What is appropriate for one is often not appropriate for the other. P.O. BOX , VICKSBURG, MISSISSIPPI / / (FAX) PAGE 3 OF 4

4 Please review the information included herein and advise if you need additional information at this particular time. I look forward to our working together, as we collectively strive to balance the recreational, aesthetic and social benefits which accrue as a result of responsible resource management at Reunion. The Power Point presentation attached to this correspondence is being provided for general dissemination to the Homeowner Association. Please let me know if you have trouble opening the presentation or in disseminating the related information. P.O. BOX , VICKSBURG, MISSISSIPPI / / (FAX) PAGE 4 OF 4

5

6 Reunion Lake View of the vertical and horizontal pvc fish structures that were placed in Reunion Lake. View of the pvc fish structures that were placed in Reunion Lake. WILDLIFE TECHNICAL SERVICES, INC. P.O. BOX VICKSBURG, MS

7 Reunion Lake View of the placement of one (1) vertical pvc fish structure in Reunion Lake. WILDLIFE TECHNICAL SERVICES, INC. P.O. BOX VICKSBURG, MS

8

9 PREPARED FOR REUNION PROPERTY OWNER ASSOCIATION

10 ELECTRO-FISHING CONDUCTED APRIL 1, 2009.

11 March 2003 Bluegill, redear, fathead minnows, grass carp, threadfin shad. June 2003 F1 Tiger Bass April 2006 Added 49 horizontal and vertical pvc fish structures. March 2006 Bluegill, redear, triploid grass carp, threadfin shad, fathead minnows. October Pre-spawn F1 Tiger Bass

12 Alkalinity of 80 parts per million (ppm). The plankton bloom slightly reduced Slight increase in turbidity levels as a result of the excessive rainfall. Visibility was measured at a depth of ~16-18 inches. While inches is recommended, turbidity within the lake is directly affecting the visibility at this time.

13

14 108 Bass sampled Forty (40) or 37% were 13 inches and less Average actual weight 1.36 pounds Average actual length inches Largest Bass 4.8 pounds and inches in length Bluegill ranged from 4 to 9 inches Lack of 1 to 3 inch bluegill Bass crowding conditions present

15 22 Bass sampled Ten (10) or 45% were 13 inches and less Average actual weight 1.29 pounds Average actual length inches Largest Bass 4.8 pounds and inches in length Bluegill ranged from 1 to 8 inches

16 Reunion Lake Remove bass 13 and less. Limit removal of bass to five (5) per angler per day. Release all bass 20 and greater. Trophy bass can be replicated by a knowledgeable taxidermist using length and girth measurements. South Lake Catch and release all bass. Harvest bluegills liberally. Encourage the aggressive removal of crappie. While fertilization is a management tool used to enhance fish production, caution is advised as an excessive plankton bloom may be aesthetically displeasing to homeowners and skiers and could pose an extreme risk of fish kill should extended periods of cloudy weather deplete the bloom thereby creating a hypoxic environment and resulting in a significant fish kill. Maintain a viable plankton bloom w/ visibility of inches. Visibility in April was inches. Turbidity levels exacerbate this measurement and are a concern. Nevertheless, while exposed shorelines and ongoing construction directly contribute to this problem, such cause/effect issues are an inevitable part of developing lakefront communities. Install a sign at the Marina with Creel Limits. Consider adding significant underwater structure as a priority lake management objective; particularly with regards to the South Lake development.

17

18