Augmentation of the Aquatic Moth, Acentria Ephemerella

Augmentation of the Aquatic Moth, Acentria ephemerella, for Control of Eurasian watermilfoil, Myriophyllum spicatum

Lincoln Pond/Milfoil Control Project Year 3 – 2002 Contract LC991923-01 LC-IM 98-02-D 0980-004-001

Prepared for: Lake Champlain Basin Program

Prepared by: Anita L. Deming (Cornell Cooperative Extension of Essex County) Index Executive Summary………………………………………………………………….. .2 Introduction...... 2 Goals for 2002....……………………………………………………………………….3 Methods Used Aquatic Plant Biomass Measurements.…………………………….……….3 Herbivore Population Surveys by Apical Stem Sampling…………………4 Combined stem length of milfoil ……………………………………………..5 Original Releases ……………………………………………………………………..5 Results of 4 years of sampling ……………………………………………………....6 Table 1 Summary of total biomass ………………………………………….7 Table 2 summary of tip sampling…………………………………..………...8 Observed Moth Impacts on Milfoil …………………………………………...9 Chart 1 Moth and Weevil Density at Lincoln Pond 2000.…………….…. 10 Chart 2 Moth and Weevil Density at Lincoln Pond 2001.…………… .….11 Chart 3 Biomass of Milfoil in 2002………...... ……………………...……12 Chart 4 Combined Stem Length of Milfoil 2002 …………………….……12

Educational Efforts……………………………………………………………….…..13 Conclusions.………………………………………………………………….……….13 Appendices. LP 2002-1 Map of release sites and GPS coordinates……………….…..14 And map of 2000 milfoil beds LP 2002-2 Lincoln Pond Aquatic biomass of control sites………………..16 LP 2002 – 3 Total Stem Length and Biomass of Milfoil in B……………...19 LP 2002 – 4 Charts of Weevil and Moth Tip Damage……………………..20 LP 2002 – 5 Educational Releases……………………………………….…26 LP 2002 – 6 Chart of Actions…………………………………………….…..31 Lincoln Pond/Milfoil 2002 Report 3

Executive Summary

Lincoln Pond is a 600-acre, modestly productive lake in Elizabethtown, NY with a spreading population of a noxious exotic plant, Eurasian watermilfoil (Myriophyllum spicatum). “Milfoil” is a nonnative plant that frustrates recreational use of water bodies and outcompetes native aquatic plants by early stem elongation that reaches the water surface quickly and forms a canopy shading the other aquatic plants. There are several insects that eat milfoil, limit its growth, and keep it from forming a canopy in some situations. One of these insects is the aquatic macrophyte moth, Acentria ephemerella. “The moth” was augmented into various areas of Lincoln Pond over two years. None of these introductions appear to have significantly changed the background levels of moths in Lincoln Pond nor to have had a significant impact on milfoil in the Pond, although there was one significant decrease in milfoil in one mid-lake plot following augmentation. Fish predation on the moths is a likely cause for their lack of survival. This study and research from other locations focus attention on the sunfish as the fish most likely to be interfering with the moth’s potential for controlling milfoil. Follow-up studies are in progress.

Introduction

Lincoln Pond: Problem and Approach Lincoln Pond is a 600-acre oligio-mesotrophic lake in Elizabethtown, NY with a maximum depth of 29 feet. There are three public boat launches, a State campground, and 103 private camps on the Pond. More than a decade ago, Eurasian watermilfoil, hereinafter referred to as “milfoil”, was introduced, presumably at one of the boat launches, and it has been spreading throughout the Pond ever since. In 1997, a detailed survey of the milfoil beds showed 118 pond acres recreationally impaired by dense milfoil. Currently, there are 23 native aquatic macrophyte species not eliminated by milfoil. There are about 450 acres of Lincoln Pond with muddy bottoms that are less than 15 feet deep, which could become covered by milfoil. Milfoil displaces native aquatic plant vegetation, chokes the water column, affects the fishery, and impairs the public use of ponds and lakes that it infests. Twenty-five camp owners have complained that they are unable to swim at their beaches without pulling milfoil three to four times per summer.

The Lincoln Pond Association and the Town of Elizabethtown prefer a natural control approach as opposed to the use of chemicals, harvesters, mats, winter drawdowns, or dredging. They agreed to work together to develop and implement a weed management plan to manage milfoil. They desired herbivores be used to control the spread of milfoil.

Cornell University’s aquatic plant researchers (Cornell University Research Ponds [CURP], Ecology and Evolutionary Biology Department) were interested in conducting a project that was well documented in order to obtain insight into the impact of milfoil herbivores and into the effects of herbivore augmentations made with milfoil control goals. Much of the existing milfoil herbivore information was confounded by other control methodologies implemented near or at the same time, or by not obtaining pre-release data on Lincoln Pond/Milfoil 2002 Report 4 the lake system involved. Results from documented milfoil weevil (Euhrychiopsis lecontei) augmentations had been and continue to be variable. We needed additional information to evaluate the success of herbivore augmentations. CURP, NY Department of Environmental Conservation staff, and our local decision making team (DMT) committee established to address the milfoil challenge and recommended studying an aquatic macrophyte moth (Acentria ephemerella; hereinafter referred to as “the moth”) as a potentially effective herbivore; Middlebury College and VT Agency of Natural Resources recommended additional studies with the milfoil weevil. Since the milfoil weevil was being studied extensively elsewhere, we opted to pursue a study with the moth.

Cornell Cooperative Extension along with Cornell University’s aquatic plant researchers released approximately 10,000 moth larvae in June 2000, 300 moth pupae and 4500 moth larvae in June 2001, and 15,000 larvae in October 2001. Our survey showed very few surviving from the 2000 release. However, survival of larvae from the 2001 releases appeared greater and was encouraging. Additional details of these releases are presented below.

Goals for 2002

 Monitor previous moth release sites to see if there were any impacts from releases for: o biomass (weight) of each species of naked eye visible aquatic plant, and o herbivorous insect activity in Lincoln Pond.

Methods Used

Aquatic Plant Biomass Measurements Milfoil biomass measurements at four Locations were compared to a baseline measurement recorded on September 8, 1999 to determine if milfoil density changed over time. Biomass measurements were taken October 14, 2000, October 20, 2001, and August 17, 2002 in 100 meters by 100 meters square (quadrat) sampling locations where the mean water depth was 1.5 – 3.0 meters. At each sampling location, we tossed a 0.25m2 quadrat frame into the water 20 times and thus selected 20 random 0.25m2 quadrat samples. A Cornell University Research Pond (CURP) diver using an air buoy underwater breathing apparatus hand-harvested all above sediment plant biomass inside each tossed quadrat frame. The diver delivered harvested samples to a boat, and we placed each sample in an individually marked plastic bag. Samples were stored on ice for transportation to the CURP laboratory. In the CURP laboratory the samples were refrigerated until analyzed unless it was determined that they could not be analyzed within two weeks, in which case they were frozen for later analysis.

At the laboratory, samples were washed and any non-plant material was removed from the sample after which the sample was separated by individual species. We oven-dried the separated plant species at 105 o C for 48 hours and measured the dry weight of each species. With these dry weights, we calculated the mean biomass for each plant species at Lincoln Pond/Milfoil 2002 Report 5 each sampled Location in the Pond. The resulting data were expressed both in terms of grams of dry weight per square meter and as a percentage of the total harvested biomass.

After the evaluation of the 1999-biomass data, and noting the small amount of variation between the sampled 0.25m2 quadrat, we tested statistically for the number of quadrats required to give us significant differences in the biomass measure. We determined that we would not loose statistical power in reducing sample size from 20 to 10 quadrats (0.25m2) because of the quadrat size measured and the small variability between sample quadrat. See Appendix LP2002 – 2 for the data sheets.

Herbivore Population Surveys by Apical Stem (“Tip”) Sampling

Insect activity was measured twice in 2002 following herbivore releases in 2000 and 2001. At each of the six Locations (A, B, C, D and B1 and B 2), 25 apical stems (“tips”) were collected and examined. This occurred on July 15th and August 5th of 2002. (See Appendix LP 2002 – 1 for map of sites.)

We collected twenty-five apical stems (top, growing part of the milfoil stem), hereafter referred to as “tips”, each having a length of 25 centimeters. Milfoil tips are the parts of the plant with the greatest number and diversity of herbivorous insects because it possesses nutritious, edible new growth and provides concealment and protection with greater leaf density. Since most milfoil herbivory is in the top 25 centimeters of the stem, a 25-centimeter sample provides a good section for quantifying herbivory.

At each sampling location, we randomly collected a series of plant stem samples using a grapple hook. We lifted the samples into the boat where we randomly selected 25 milfoil stems from the milfoil plant samples by choosing the basal end (to ensure the choice was “blind”). We then pinched off the top 25 cm of each stem for our apical stem (“tip”) sample. We placed each tip sample into an individually marked plastic zipper bag labeled with an identification number, the sample location, and date. We stored all tips on ice in an insulated chest for transport to the CURP laboratory.

In the laboratory we refrigerated all samples that we planned to analyze within two weeks and froze all others. At the time of examination, we placed each tip under a stereoscopic dissecting microscope. We dissected each tip recording numbers of each herbivore, life stage(s) present, and an evaluation of the entire tip which included evidence of herbivore use (retreats, cocoons, or pupal chambers), and milfoil tissue damage (leaflet damage, stem mining, missing or grazed buds).

For each tip, we made a quality assessment and quantified all milfoil tissue damage using a CURP standard scoring system. Using this standard CURP protocol, we are able to determine which herbivore (moth, weevil, Caddisfly or midges) was most likely responsible for which damage and to assess the amounts of damage caused the milfoil by each of the herbivores. Lincoln Pond/Milfoil 2002 Report 6

The baseline tip surveys were completed in June 17, July 29, and August 9 of 1999. Additional tip surveys were made on May 25, June 15, 8 July, 5 August, and 16 September 2000; June 23, July 2, August 18, and October 18, 2001; and July 15 and August 5, 2002.

Combined Stem Length of Milfoil

The biomass samples that were collected from the 10 quadrats were measured for length of plants in centimeters. Each length was combined with the others of the same species and reported as combined tip length. This measurement was added at the end as there seemed to be a shortening of the milfoil in the one release site B2. This was confirmed by comparing the control B and the treatment plot B1 (summer of 2001 release only).

Original Releases

In 1978 a survey of Lincoln Pond showed that there was no appreciable milfoil anywhere in the lake. In the mid 1980’s the County lowered the water level to repair the causeway between the two sections of the lake. Following the draining of the northern section of the lake, shore owners began to complain of a weed that was impacting the mid section of the lake. It was identified as Eurasian watermilfoil. In 1993 Robin Ulmer of the Boquet River Association mapped about 60 acres of “impacted” lakebed. In 1997, John Deming Land Surveyor and Steve Lamere, Certified Lake Ecologist, mapped 118 acres of dense milfoil beds. In 2000, John Deming, Land Surveyor, and Robert Johnson mapped 137.85 acres of dense milfoil.

It appears that the draining of the lake stressed the native vegetation and allowed the few milfoil plants that were there to gain an advantage. Once started they have been spreading down stream and along the shoreline where boaters “brought it home” after boating through the “beds.” We extrapolate the spread of impacted acreage at 5%/year. There are about 400 acres (66% of the Lake) of potential milfoil habitat in Lincoln Pond (soft substrate less than 14 feet deep). So far the deepest we have measured milfoil growing is 14 feet.

Site A, C and D are newer sites of infestation. Site B is believed to be the first site as it is at the boat launch. Site B is also the greatest acreage of milfoil and goes into the deepest water. Initially we did our releases in Site D as it was the lushest and densest bed. However, we changed our strategy to Site B when we saw the greatest number of naturally occurring Acentria were at that site.

Herbivores released were raised at the Cornell University Research Ponds (CURP) in Ithaca during winter and spring of 2000 and 2001. Please see Appendix LP 2002 – 1 for a map of the lake and locations of beds and release sites and Appendix LP 2002-6 for a summary of releases at each site.

1st - On June 14, 2000, we selected milfoil stems from the CURP greenhouse with healthy small (2nd instar [growth stage]) moth larvae attached and planted them in small peat pots Lincoln Pond/Milfoil 2002 Report 7 which were lowered into Lincoln Pond two days later. We released approximately ten thousand (between 8,500 and 11,500) moth larvae on June 16, 2000 in Plot B. The release sites were 100 square meters (10 meters by 10 meters) each within Plot D, EE and FF (as displayed in Appendix LP 2002 - 1) (between 4,250 to 5750 larvae at each site) with two other sites used as short-term controls. However, there were no significant moth results at EE or FF.

2nd - On June 22, 2001, we released 300 pupae (nearly adult moth larvae in cocoons) at Location D where we released younger moth larvae in 2000. While such numbers were nearly insignificant, we wanted to observe any resulting increases in moth populations at Location D. They were released between the original sites EE and FF along the midline. The data is reported as M. However, there were no significant results from M.

3rd - We selected later instar moth larvae for another augmentation, anticipating increased moth larvae survival. We projected that an earlier established, more robust population of moth larvae would be able to compete more successfully with early weevil populations.

On June 22, 2001, we added moth larvae to a new plot in the northern half of the lake at Location B, which we had monitored with herbivore surveys since 1999. Location B had similar milfoil densities to Location D, and is the location where lakeshore owners believe milfoil first entered the Pond. We recorded a small indigenous population of moths at Location B in 2000. Since earlier releases were in Plots EE and FF at Location D with a density of weevils, we released moth larvae in Location B to avoid weevil interference or confounding data from the earlier release. Augmentation at this site provided an opportunity to determine if augmenting a small existing population of moth larvae would be an effective method of establishing larger populations. We released 4500 2nd and 3rd instar (growth stage) moth larvae in Plot B1 and B2 at Location B. We sampled stems at Location B on August 18, 2001.

4th - In the fourth 2001 augmentation, on October 19, we released 15,000 2nd and 3rd instar moth larvae, in a resting state, into Plot B2 (10 meters by 10 meters) within Location B. We left B1 for any long term impact from the 3rd release. Release method and timing were used to avoid larvae loss due to fish predation since we suspected fish predation was a major interference with our earlier augmentations.

Results of 4 years of sampling

Biomass There is quite a range of grams of dry weight per meter squared (g DW/m²) of milfoil and other vegetation from year to year even in the control areas. This has a lot to do with the warmth of the summer and sunlight and the time of year. We could not attribute any specific benefit to the Acentria releases.

Control Site A had a decrease in milfoil percent and grams of dry weight of milfoil. Control parts of Sites B, C, and D actually had an increase in the Dry weight of milfoil. Lincoln Pond/Milfoil 2002 Report 8

Table 1. Summary of total biomass. g DW/m² = grams of dry weight per meter squared.

Site g DW/m² of vegetation g DW/m² of milfoil % milfoil % bladderwort

1999 – control year A 76.91 69.56 90.4 0.8 B 50.28 27.23 54.2 18.5 C 85.36 67.61 79.2 5.4 D 37.28 30.09 80.7 3.8

2000 A 29.36 24.31 82.8 5.0 B 64.13 20.03 31.2 38.5 C 56.35 31.54 56.0 24.0 D 59.72 56.39 94.4 0.0

2001 A 27.20 19.83 72.9 3.7 B 56.50 21.47 38.0 25.6 C 47.04 27.54 58.6 13.6 D 58.26 54.98 94.4 0.0

2002 A 63.04 32.39 51.4 0.3 B 86.58 55.69 64.3 3.0 Control Plot B 66.33 Plot B1 57.66 Plot B2 24.72 C 128.38 111.04 86.5 0.9 D 141.02 135.42 96.0 0.06

Lincoln Pond/Milfoil 2002 Report 9

Table 2 Summary of Tip Sampling:

Summary of moth and weevil numbers by date from 1999 to 2002. Numbers are insects per 25 apical stem (“tip”) samples found at Location: A, B, C, D, in treated plots EE and FF at location D, and in plots B1 and B2 at location B.

We performed three exploratory herbivore surveys in June, July and August of 1999, before the release of any milfoil moth caterpillars, and found evidence 8 times of moth activity (average 0.02 per stem) and few weevils (0.12 per stem). Previous work in NY showed that the weevil seemed to prefer smaller water bodies and the moth was found in larger lakes. We found very few of either. In 2000, after our early release of small young larvae, we saw evidence of moth activity twice at our release site EE and FF, but a large number of weevils had came in on their own. There was no decrease in the overall biomass over the years from this intense infestation of weevils. In 2001 the evidence of moth survival was poor. Only site B was showing any moths through that summer, and they were from a “natural” population. We decided to try a mid summer release of larger moth larvae at two new sites B1 and B2. However, the tip sampling did not show any evidence of moth activity in October of 2001. Lincoln Pond/Milfoil 2002 Report 10

As a last resort, we tried a fall release of “resting” larva in October of 2001 only at site B2. The following summer, we did see evidence of herbivory, but few insects themselves remained. Also, we saw a visible difference in the density and length of the milfoil in the fall release site B2. We believed the caterpillars did their damage early in the spring when the milfoil was small and prevented the rapid elongation. In the biomass sampling there is a dramatic change in the weight of milfoil and the total tip length of milfoil in the release site B2, compared to the surrounding control of Site B and adjacent plot B1 where only a summer release was made.

Observed Moth Impacts on Milfoil 2000 Our first two surveys of 2000 revealed few herbivores (average of 0.07 moth larvae and 0.08 weevils per stem). Therefore, we decided that Lincoln Pond would be a good candidate to test augmentation. Since there were few insects to start with, we anticipated an increased population of moths.

On July 8, the first post-augmentation herbivore survey on plots EE and FF yielded unexpected results. We found few moth larvae, but more milfoil weevils were present than we had counted in previous Lincoln Pond surveys. The milfoil weevil count, 0.34 per stem, continued to rise in subsequent surveys. In this first survey, we found moderate to high levels of milfoil weevil damage and some less frequent indications of moth damage on the milfoil plants.

We recorded a large increase in milfoil weevils on tips (average of 0.84 per stem) at Locations C, D, and at our moth augmentation Plots EE and FF, both within Location D, in the August 5 survey. This population of milfoil weevils at Locations C and D was significant. Our final survey on September 16 revealed no moth larvae, and only a few milfoil weevils, as most milfoil weevil adults had gone to shore for the winter. Many milfoil stems from this last survey had milfoil weevil damage while some displayed new, late-season regrowth. It was clear that there were more milfoil weevils than moth larvae in Lincoln Pond. Nevertheless, neither reached the theoretical critical mass of one per stem for moth larvae or three per stem for milfoil weevils. The populations varied over the summer. Location B revealed the most moth herbivory. Locations C and D showed the most weevil herbivory.

The year 2000 moth augmentation was not a success, but did yield insights into the moth augmentation process. The unexpectedly large population of milfoil weevils in Lincoln Pond was an important factor in our research that had to be considered. During 2000, we recorded aquatic moth larvae in Lincoln Pond, however, they appeared to be naturally occurring, and not the result of our augmentation at Plots EE and FF. We evaluated our observed herbivore population differences between locations and dates statistically. We moved our focus to the influence of milfoil weevils on moth populations.

2001 In 2001 milfoil weevils again out numbered moths in Lincoln Pond. Location B continued to hold the largest population of moth larvae, but that was a natural population as Lincoln Pond/Milfoil 2002 Report 11 none were augmented in that Location until after the July 2, 2001 tip sampling when they were added to Plots B1 and B2 We were unable to find any evidence of a moth population increase at Location D on the August 18 sampling following the introduction of 300 pupae in June. The results of that stem sample survey revealed only a few moth larvae in Plots B1 and B2 at Location B. There was no significant increase over expectations for indigenous moth larvae. 2002. Once again weevils out numbered the moths and tip sampling showed no significant increase in the moth larva populations using our methodology.

Chart 1 Moth and Weevil Density on Apical Stems in 2000 Lincoln Pond/Milfoil 2002 Report 12

Moth Populations at Lincoln Sites A - FF

1.0 Moth larvae added 6/16 n=25 apical 0.9 at D into two locations stems EE and FF + 1SE m 0.8 e t y 0.7 t S i

s l 0.6 B a n B c e

i 0.5 D p 0.4 A h

o 0.3 s h M 0.2 B B t o 0.1 A C FF EE M 0.0 A C D A C D D DD EE A C D FF A B C D EE FF 5/25 6/15 7/08 8/05 9/16 2000

Weevil Populations at Lincoln Sites A - FF

Moth larvae added 6/16 EE n = 25 apical at D into two locations FF stems 1.0 + 1SE

m EE and FF e t

y C D t S i

n C c e i D p

A 0.5 DD i B EE v / C

B e s e l

W D EE e FF D e B A A B

W A C D D A C FF 0.0 5/25 6/15 7/08 8/05 9/16 2000 Lincoln Pond/Milfoil 2002 Report 13

Chart 2 Moth and Weevil Density on Apical Stems in 2001

Moth Populations at Lincoln Sites A - D, M

1.0 Added moth pupae n=25 apical 0.9 into D on EE center stems + 1SE m 0.8 line on 7/02 e Added moth t y t

S 0.7 i

larvae into s l a n 0.6 B1 on 6/22 c e i 0.5 D p

0.4 t /

s 0.3 h M t 0.2 o 0.1 B B M 0.0 A C D A C D A C D M 6/23 7/02 8/18 2001

Weevil Populations at Lincoln Sites A - D, M

D n = 25 apical D stems + 1SE

m 1.0 e t y S t

i l s a n c e i p D

A l A B 0.5 i B C / C v s e l

e B i C v W e A

W A D 0.0 6/23 7/02 8/18 2001

M is the midline between EE and FF. Lincoln Pond/Milfoil 2002 Report 14

Chart 3 and 4 There is a significant difference in the combined stem length and in the biomass in plot B2 from the B1 summer application and the control B. Mean (n = 10 sampled quadrats) combined stem length (cm) of all milfoil per 0.25m2 quadrate (top), and mean (n = 10 sampled quadrats) dry biomass (g) of all milfoil per m2 (bottom), as the result of treatments with and without Acentria additions. Treatments labeled with different letters are significantly different (MWW, p<0.0005).

Chart 3 Milfoil Biomass of milfoil in 2002 in Control Site B and B1 and fall treatment B2

Moth Reduces Watermilfoil Biomass

100 4500 larvae +1SE June 22, 2001 n = 10 )

a 2 15,000 larvae on m

g Oct. 19, 2001 (

s 50 a m

o b i B

0 Control B B1 B2 July 15, 2002

Chart 4. Combined Stem Length of Milfoil in control site B and B1 and fall treatment B2

Moth Reduces Watermilfoil Stem Length

10000 +1SE )

m n = 10

t a g n e L

5000 m e t

l a t o T 0 Control B B1 B2 Treatment Lincoln Pond/Milfoil 2002 Report 15

Educational Efforts

Several web sites have been developed presenting several stages of this research. Once this report is approved we will add it to the sites and

Several web sites have been developed. Please see:

 www.eeb.cornell.edu/ponds/page  http://www.fw.umn.edu/research/milfoil/milfoilbc.html  http://www.cce.cornell.edu/essex/milfoil/milfoil.html  http://cce.cornell.edu/counties/Essex/milfoil/moth.html

Please see Appendix LP 2002 - 4 Two Press Releases were developed describing milfoil moth and fish predation and promoting a sunfish derby. A handout for landowners around the lake and for campers at the State Campsite were developed and distributed. An Article was developed and was distributed through the North Adirondack Agricultural News (3500), Town and Country (900), Boquet River Association Newsletter (300), and Au Sable River Association (250). Two public service announcements were developed for WIPS in Crown Point and Ticonderoga and a half hour interview was conducted on August 2003.

Conclusions

This moth augmentation project generated interest from lake associations state-wide. The concept that an insect already present in NY could control the noxious milfoil plant is attractive since it would involve modest expense and would be environmentally safe. Several groups are looking for more information on our project.

We cannot claim success since we have not produced an increased population of moths capable of exerting widespread control. We did, however, document an adverse impact on milfoil (reductions in stem length and biomass) in plots where moths were introduced. Our focus is increasingly directed toward fish predation as the interfering agent in our augmentation process.

Milfoil herbivore predation probably comes from a number of animals representing various taxonomic groups. We need not, however, focus on all predators. We should identify those predators that exert significant control on milfoil herbivores. Predation by sunfish may be a key limiting factor on moth herbivory success. This contention is supported by data from studies in Lebanon Reservoir, from observations and studies made at the CURP ponds, and aquaria observations made by Robert Johnson that occupied macrophyte moth refuges, originally present when sunfish were introduced to aquaria with milfoil and aquatic macrophyte moths, were missing from milfoil stems at the end of the experiment. N

Lincoln Pond/Milfoil 2002 Report 16

Appendix LP 2002-1 Scale 1 to 22,400 or 0.5 inches = 500 m Lincoln Pond Moth Augmentation Sites

Scale: 1 : 22,400 500 m Lincoln Pond/Milfoil 2002 Report 17

Map of Lincoln Pond Milfoil beds 2000 Lincoln Pond/Milfoil 2002 Report 18

Appendix LP 2002 – 2

Lincoln Pond Aquatic Plant biomass on 8-17-2002 Quadrat (0.50m*0.50m) Species Composition and Species Dry Weight (g/0.25m2)

Location A 2002

SITE PLANT SPECIES DW02-1 DW02-2 DW02-3 DW02-4 DW02-5 DW02-6 DW02-7 DW02-8 A ELODEA CANADENSIS 2.57 1.83 1.26 2.38 2.95 0.77 1.40 0.58 A MYRIOPHYLLUM SPICATUM 9.73 10.05 15.26 0.45 8.27 0.01 16.60 15.93 A NIJAS FLEXILIS 0.00 0.04 0.05 0.16 0.11 0.48 0.00 0.01 A NITELLA ssp. 0.03 0.00 0.05 0.04 1.38 0.08 0.00 0.05 A POTAMOGETON PRAELONGUS 0.00 0.00 0.00 0.09 0.28 0.00 0.00 0.00 A POTAMOGETON PUSILLUS 0.12 0.01 0.03 0.03 0.37 0.00 0.01 0.05 A UTRICULARIA spp. 0.01 0.00 0.00 0.00 0.01 0.21 0.00 0.17 A VALLISNERIA AMERICANA 2.09 4.12 5.31 9.41 5.94 9.30 4.82 0.00 TOTAL 14.55 16.05 21.97 12.56 19.31 10.85 22.83 16.79

DW02-9 DW02-10 tot02DW %02DW g/.25m² gDW/m² A ELODEA CANADENSIS 3.29 2.78 19.81 12.57 1.98 7.92 A MYRIOPHYLLUM SPICATUM 0.31 4.36 80.97 51.38 8.10 32.39 A NIJAS FLEXILIS 0.00 0.00 0.85 0.54 0.09 0.34 A NITELLA ssp. 0.08 1.62 3.34 2.12 0.33 1.34 A POTAMOGETON PRAELONGUS 0.00 0.00 0.36 0.23 0.04 0.15 A POTAMOGETON PUSILLUS 0.07 0.05 0.74 0.47 0.07 0.29 A UTRICULARIA spp. 0.00 0.00 0.40 0.26 0.04 0.16 A VALLISNERIA AMERICANA 3.96 6.18 51.13 32.44 5.11 20.45 TOTAL 7.71 14.99 157.61 100.00 15.76 63.04

Location B 2002

SITE PLANT SPECIES DW02-1 DW02-2 DW02-3 DW02-4 DW02-5 DW02-6 DW02-7 DW02-8 B CHARA VULGARIS 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 B ELODEA CANADENSIS 0.37 0.21 0.38 0.22 0.38 2.33 0.08 0.40 B MYRIOPHYLLUM SPICATUM 12.48 8.45 21.47 7.92 6.17 21.48 11.17 10.63 B NAJAS FLEXILIS 0.00 0.00 0.15 0.12 0.03 0.06 0.05 0.31 B NITELLA ssp. 0.11 0.02 0.11 0.22 0.00 0.10 0.01 0.03 B POTAMOGETON AMPLIFOLIUS 0.00 8.68 1.29 0.13 8.97 0.00 8.36 0.00 B POTAMOGETON PRAELONGUS 0.00 1.83 1.97 0.00 0.00 0.00 0.00 0.00 B POTAMOGETON PUSILLUS 0.02 0.01 0.00 0.01 0.06 0.03 0.00 0.00 B SAGITTARIA ssp. 0.15 0.00 0.25 0.21 2.87 0.00 0.43 0.96 B UTRICULARIA ssp. 0.94 0.43 0.60 1.98 0.30 0.10 1.29 0.55 B VALLISNERIA AMERICANA 0.89 4.55 0.36 1.24 3.85 1.91 0.01 3.97 TOTAL 14.96 24.19 26.58 12.04 22.63 26.02 21.40 16.87 Lincoln Pond/Milfoil 2002 Report 19

DW02-9 DW02-10 tot02DW %02DW g/.25m² gDW/m² B CHARA VULGARIS 0.01 0.00 0.01 0.01 0.00 0.00 B ELODEA CANADENSIS 0.16 0.52 5.05 2.34 0.51 2.02 B MYRIOPHYLLUM SPICATUM 17.98 21.47 139.22 64.32 13.92 55.69 B NAJAS FLEXILIS 0.08 0.08 0.88 0.41 0.09 0.35 B NITELLA ssp. 0.00 0.03 0.64 0.29 0.06 0.25 B POTAMOGETON AMPLIFOLIUS 3.01 0.26 30.69 14.18 3.07 12.28 B POTAMOGETON PRAELONGUS 0.09 0.00 3.89 1.80 0.39 1.56 B POTAMOGETON PUSILLUS 0.03 0.00 0.17 0.08 0.02 0.07 B SAGITTARIA ssp. 0.48 0.00 5.35 2.47 0.53 2.14 B UTRICULARIA ssp. 0.13 0.14 6.47 2.99 0.65 2.59 B VALLISNERIA AMERICANA 4.86 2.44 24.08 11.12 2.41 9.63 TOTAL 26.83 24.95 216.44 100.00 21.64 86.58

Location C 2002

SITE PLANT SPECIES DW02-1 DW02-2 DW02-3 DW02-4 DW02-5 DW02-6 DW02-7 DW02-8 C ELODEA CANADENSIS 0.03 0.55 0.08 0.07 0.02 0.05 0.92 0.01 C MYRIOPHYLLUM FARWELLII 0.00 0.00 0.00 0.36 0.00 30.19 0.00 0.00 C MYRIOPHYLLUM SPICATUM 38.44 32.84 39.00 27.42 21.22 0.02 29.66 27.22 C NAJAS FLEXILIS 0.02 0.02 0.00 0.07 0.00 0.00 0.01 0.00 C NITELLA ssp. 1.14 0.41 0.06 0.42 0.08 0.09 0.21 0.05 C POTAMOGETON AMPLIFOLIUS 0.00 0.97 0.00 0.00 0.00 0.00 0.00 0.00 C POTAMOGETON PUSILLUS 0.00 0.01 0.00 0.00 0.00 0.00 0.02 0.00 C SAGITTARIA ssp. 0.00 0.00 0.00 0.00 1.27 0.52 0.32 0.05 C UTRICULARIA ssp. 0.03 0.32 0.45 0.04 0.12 0.40 0.02 0.01 C VALLISNERIA AMERICANA 0.00 0.02 0.00 1.19 0.00 0.00 0.00 0.00 TOTAL 39.66 35.12 39.59 29.56 22.71 31.26 31.15 27.34

DW02-9 DW02-10 tot02DW %02DW g/.25m² gDW/m² C ELODEA CANADENSIS 0.19 0.08 2.01 0.62 0.20 0.80 C MYRIOPHYLLUM FARWELLII 0.00 0.02 30.57 9.52 3.06 12.23 C MYRIOPHYLLUM SPICATUM 22.74 39.04 277.60 86.49 27.76 111.04 C NAJAS FLEXILIS 0.00 0.03 0.14 0.04 0.01 0.05 C NITELLA ssp. 0.14 0.13 2.73 0.85 0.27 1.09 C POTAMOGETON AMPLIFOLIUS 0.00 0.00 0.97 0.30 0.10 0.39 C POTAMOGETON PUSILLUS 0.00 0.06 0.09 0.03 0.01 0.04 C SAGITTARIA ssp. 0.58 0.00 2.74 0.85 0.27 1.10 C UTRICULARIA ssp. 0.21 1.30 2.88 0.90 0.29 1.15 C VALLISNERIA AMERICANA 0.00 0.04 1.25 0.39 0.12 0.50 TOTAL 23.86 40.70 320.96 100.00 32.10 128.38 Lincoln Pond/Milfoil 2002 Report 20

Location D 2002

SITE PLANT SPECIES DW02-1 DW02-2 DW02-3 DW02-4 DW02-5 DW02-6 DW02-7 DW02-8 D ELODEA CANADENSIS 0.48 1.18 1.83 1.36 0.10 0.98 0.18 0.35 D MYRIOPHYLLUM FARWELLII 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 D MYRIOPHYLLUM SPICATUM 29.43 36.58 35.29 30.26 46.68 23.59 26.85 39.59 D NAJAS FLEXILIS 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 D NITELLA ssp. 0.03 0.03 0.08 0.05 0.03 0.07 0.22 0.04 D POTAMOGETON AMPLIFOLIUS 0.00 1.91 0.56 0.00 0.00 0.05 0.00 0.01 D POTAMOGETON PUSILLUS 0.01 0.00 0.04 0.01 0.00 0.05 0.01 0.00 D SAGITTARIA ssp. 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 D UTRICULARIA ssp. 0.03 0.00 0.02 0.02 0.01 0.03 0.00 0.09 D VALLISNERIA AMERICANA 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 TOTAL 29.98 39.71 37.81 31.70 46.83 24.75 27.26 40.08

DW02-9 DW02-10 tot02DW %02DW g/.25m² gDW/m² D ELODEA CANADENSIS 0.09 0.17 6.71 1.90 0.67 2.69 D MYRIOPHYLLUM FARWELLII 0.00 0.00 0.00 0.00 0.00 0.00 D MYRIOPHYLLUM SPICATUM 37.32 32.96 338.55 96.03 33.86 135.42 D NAJAS FLEXILIS 0.00 0.00 0.01 0.00 0.00 0.00 D NITELLA ssp. 0.05 0.15 0.73 0.21 0.07 0.29 D POTAMOGETON AMPLIFOLIUS 1.42 1.37 5.32 1.51 0.53 2.13 D POTAMOGETON PUSILLUS 0.02 0.01 0.15 0.04 0.01 0.06 D SAGITTARIA ssp. 0.00 0.66 0.66 0.19 0.07 0.26 D UTRICULARIA ssp. 0.01 0.00 0.20 0.06 0.02 0.08 D VALLISNERIA AMERICANA 0.00 0.21 0.21 0.06 0.02 0.08 TOTAL 38.91 35.51 352.54 100.00 35.25 141.02 Lincoln Pond/Milfoil 2002 Report 21

Appendix LP 2002-3 Total stem length (cm / 0.25m2) and dry biomass (g / m2) from 7/15/02 comparing the control plot B to a summer 2001 moth augmentation plot B 1 and a fall 2001 moth augmentation plot B 2. Ten 0.25m2 samples above sediment are reported below for total length and dry biomass.

Sample B total stem length (cm/0.25m2) B1 total stem length (cm/0.25m2) B2 total stem length (cm/0.25m2) 1 7307 7251 3852 2 4281 4975 2285 3 11705 4434 3092 4 7706 5228 813 5 5685 6832 2491 6 3444 7573 1891 7 11498 7360 1929 8 5204 4922 2690 9 7093 4340 3485 10 5375 9274 3022

Mean 6930 6219 2555 Stdev 2800 1661 883

Sample B biomass (g/m2) B1 biomass (g/m2) B2 biomass (g/m2) 1 69.4 67.08 33.2 2 51.8 50.52 26.72 3 92.24 43.92 40.2 4 72.76 46.96 0.19 5 56.92 56.6 26.08 6 29 73.2 21.48 7 123.4 59.16 25.72 8 51.04 46.2 18.44 9 71.24 43.56 29.8 10 45.52 89.36 25.32

Mean 66 58 25 Stdev 27 15 11 Lincoln Pond/Milfoil 2002 Report 22

Appendix LP 2002 – 4 Charts of Weevil and moth tip damage by location.

Estimated Weevil Populations at Location A 1.0 +-1SE 0.9 n=25 m

e 0.8 t S

0.7 l a

c 0.6 i p 0.5 A

0.4 s l i

v 0.3 e

W 0.1 0.0

7/15 8/5 2002

Herbivore Damage to Milfoil at Location A

g 0 +1SE Healthy

t n=25 a R

e 1 Minor g a m a

D 2 Moderate

m e t S

Extensive

l 3 a c i p

A 4 Destroyed

7/15 8/5 2002

Figure C-20. Mean weevils (all life stages) ± 1SE recorded per 25cm apical stem at Location A (n = 25 apical stems). Herbivore damage to 25cm apical stems (“tips”)of milfoil at Location A shown as a mean rating ± 1SE of herbivore damage to 25 apical stems. Herbivore damage ranges from 0 = no damage to 4 = apical tip destroyed. Lincoln Pond/Milfoil 2002 Report 23

Estimated Weevil Populations at Location B 1.0 +-1SE 0.9 n=25 m

e 0.8 t S

0.7 l a

c 0.6 i p 0.5 A

0.4 s l i

v 0.3 e

W 0.1 0.0

7/15 8/5 2002

Herbivore Damage to Milfoil at Location B

g 0 +1SE Healthy

t n=25 a R

e 1 Minor g a m a

D 2 Moderate

m e t S

Extensive

l 3 a c i p

A 4 Destroyed

7/15 8/5 2002

Figure C-21. Mean weevils (all life stages) ± 1SE recorded per 25cm apical stem at Location B (n = 25 apical stems). Herbivore damage to 25cm apical stems (“tips”)of milfoil at Location B shown as a mean rating ± 1SE of herbivore damage to 25 apical stems. Herbivore damage ranges from 0 = no damage to 4 = apical tip destroyed. Lincoln Pond/Milfoil 2002 Report 24

Estimated Moth Populations at Location B 1.0 +-1SE 0.9 n=25 0.8 m e

t 0.7 S

l 0.6 a c

i 0.5 p

/ 0.3 h t

M 0.1 0.0

7/15 8/5 2002

Herbivore Damage to Milfoil at Location B

g 0 +1SE Healthy

t n=25 a R

e 1 Minor g a m a

D 2 Moderate

m e t S

Extensive l 3 a c i p

A 4 Destroyed

7/15 8/5 2002

Figure C-22. Mean moths (all life stages) ± 1SE recorded per 25cm apical stem at Location B (n = 25 apical stems). Herbivore damage to 25cm apical stems (“tips”)of milfoil at Location B shown as a mean rating ± 1SE of herbivore damage to 25 apical stems. Herbivore damage ranges from 0 = no damage to 4 = apical tip destroyed. Lincoln Pond/Milfoil 2002 Report 25

Moth Augmented on October 19, 2001 Estimated Weevil Populations at Location B2 1.0 +-1SE 0.9 n=25 m

e 0.8 t S

0.7 l a

c 0.6 i p 0.5 A

0.4 s l i

v 0.3 e

W 0.1 0.0

7/15 2002

Moth Augmented on October 19, 2001 Herbivore Damage to Milfoil at Location B2

g 0 +1SE Healthy

t n=25 a R

e 1 Minor g a m a

D 2 Moderate

m e t S

Extensive l 3 a c i p

A 4 Destroyed

7/15 2002

Figure C-23. Mean weevils (all life stages) ± 1SE recorded per 25cm apical stem at Plot B2 (n = 25 apical stems). Herbivore damage to 25cm apical stems (“tips”)of milfoil at Plot B2 shown as a mean rating ± 1SE of herbivore damage to 25 apical stems. Herbivore damage ranges from 0 = no damage to 4 = apical tip destroyed. Lincoln Pond/Milfoil 2002 Report 26

Herbivore Damage to Milfoil at Location C

g 0 +1SE Healthy

t n=25 a R

e 1 Minor g a m a

D 2 Moderate

m e t S

Extensive

l 3 a c i p

A 4 Destroyed

7/15 8/5 2002

Estimated Weevil Populations at Location C 1.0 +-1SE 0.9 n=25 m

e 0.8 t S

0.7 l a

c 0.6 i p 0.5 A

0.4 s l i

v 0.3 e

W 0.1 0.0

7/15 8/5 2002

Figure C-24. Mean weevils (all life stages) ± 1SE recorded per 25cm apical stem at Location C (n = 25 apical stems). Herbivore damage to 25cm apical stems (“tips”)of milfoil at Location C shown as a mean rating ± 1SE of herbivore damage to 25 apical stems. Herbivore damage ranges from 0 = no damage to 4 = apical tip destroyed. Lincoln Pond/Milfoil 2002 Report 27

Estimated Weevil Populations at Location D 1.0 +-1SE 0.9 n=25 m

e 0.8 t S

0.7 l a

c 0.6 i p 0.5 A

0.4 s l i

v 0.3 e

W 0.1 0.0

7/15 8/5 2002

Herbivore Damage to Milfoil at Location D

g 0 +1SE Healthy

t n=25 a R

e 1 Minor g a m a

D 2 Moderate

m e t S

Extensive

l 3 a c i p

A 4 Destroyed

7/15 8/5 2002

Figure C-25. Mean weevils (all life stages) ± 1SE recorded per 25cm apical stem at Location D (n = 25 apical stems). Herbivore damage to 25cm apical stems (“tips”)of milfoil at Location D shown as a mean rating ± 1SE of herbivore damage to 25 apical stems. Herbivore damage ranges from 0 = no damage to 4 = apical tip destroyed. Lincoln Pond/Milfoil 2002 Report 28

Appendix LP 2002 – 5 – Press Releases PRESS RELEASE: Immediately TITLE: Lincoln Pond Fishing Derby The Lincoln Pond Association is announcing cash awards for the most sunfish caught and the most weight of sunfish caught at Lincoln Pond this weekend. In each category first place will be $30, second is $20 and third is $10. The awards will be made at 6 PM at the boat launch next to the Lincoln Pond Rd just west of the causeway. You may bring in your fish from 3 PM to 6 PM or make arrangements with Anita Deming (873-2178 home or 962-4810 work) to deliver your fish earlier. You may catch your fish at any time from now until Sunday, but please freeze them if they are not fresh. For the size category we will use a scale. For the number category we will count all fish no matter how small. The sunfish in Lincoln Pond are stunted because the lake is out of sync with its carrying capacity. There are so many sunfish that they are eating the milfoil moth caterpillars that we have released to help control the milfoil. We are trying this fishing derby to bring the lake back into an ecologically sustainable balance. Also as a part of this effort, we are asking for a voluntary catch and release on large bass. The large bass are very efficient at eating small sunfis so we are hoping to have more of them in the lake for longer.

TITLE: Lincoln Pond Pan-Fishing Derby Author: Anita Deming, Lincoln Pond Association There were 6 winners of the Lincoln Pond Pan-Fishing Derby last Sunday. A total of 378 fish were caught at a total weight of 30.3 pounds. This means the average fish was only 1.28 ounces. Pan fish this small are indicative of stunted fish that do not have enough to eat. There were only 3 Crappies caught, and 25 yellow perch, the rest were pumpkinseeds. We were surprised that there were no bluegills at all. The winner for most fish was Matt Little who caught 75 fish. The winner of most weight was Edward Paquin with 6 pounds and 3 ounces. Second place winners were Mike O’Day and Rachel Deming. Third place winners were Patrick and Kayla Ellsworth. The Lincoln Pond Association sponsored this contest to publicize the problem with too many small fish in Lincoln Pond. These small fish survive on insects, but the Lincoln Pond Association is trying to use insects to control the milfoil. Therefore, we are looking for more large fish and are asking for a voluntary catch and release on the Bass in Lincoln Pond. The Bass are our best predator for eating the sunfish once they are legal to take. Consider leaving them to grow another 3 or 4 inches before you take them and we will have a superb trophy bass fishery, and better milfoil control The Lincoln Pond Association is interested in hearing from fisherman, if they would like to have a trophy bass fishery at Lincoln Pond. This would mean raising the legal size for take home. Please call Anita Deming at 962-4810 or write PO Box 37 New Russia NY 12964 to comment. Lincoln Pond/Milfoil 2002 Report 29

Lincoln Pond Association President Steve Muller PO Box 131 Elizabethtown NY 12932 (518) 873-6500 days (518) 942-3310 evenings [email protected] To: Lincoln Pond Campers The Lincoln Pond Association welcomes you to our wonderful lake. Please take a moment to review these suggestions to help us keep this a memorable experience for all.

Aquatic Pests (Milfoil, Zebra Mussels, and Water Chestnuts) Milfoil has choked over 200 acres of our 600-acre lake. We are participating in a Cornell University and Lake Champlain Basin Program study releasing Acentria ephemerella (milfoil moth) to control the milfoil naturally. However, we suspect that the sunfish (especially pumpkinseeds and yellow perch) are eating many of our moth caterpillars. To reduce predation, keep all of the pan fish you catch and dispose of them properly (eating them fried in beer batter works or you could bury them on land). We do not have Zebra Mussels or Water Chestnut yet and we ask you clean all weeds and other organisms from your boats and trailers before launching in Lincoln Pond. All bilge water and bait boxes should be drained and air-dried for a week. Scrape off any Zebra Mussels and remove any plant or animal material from boats and trailers.

********************Fishing Request*****Please**************************** We are requesting a VOLUNTARY CATCH AND RELEASE OF BASS until they are 16 inches instead of 12 inches. This will give them a few more years to eat the pan fish before they are removed, and you can have trophy size fish next year. Once again we are asking all fishermen to remove any pan fish that they catch. **************************************************************************

Boaters 1. Clean you boat before entering and after leaving Lincoln Pond. We need your help in preventing the spread of milfoil and the introduction of water chestnut and zebra mussels. It is NYS law not to transport noxious species from one lake to another. 2. NY State Law says 5 mph within 100 feet of shore, docks, piers, rafts, floats or anchored boats or within 500 feet of a roped off swimming area. 5 mph means no wake. In Lincoln Pond the area between the causeway and the island, and the narrows at the north end by the dam are less than 200 feet wide and therefore are no wake zones. 3. Stay 100 feet from all other boaters, anchored boats, swimmers, and fishermen. 4. NY State Law says personal watercraft or “jet ski” operators must be 21 years old or have a “Certificate of Instruction.” Lincoln Pond/Milfoil 2002 Report 30

5. Remember there are others that do not want to hear constant motor noise all day. We are asking recreational users, such as water skiers and jet skiers, to only operate between the hours of 10 AM and 6 PM. This will let the fisherman fish in peace and quiet, and late sleepers get a few extra winks. 6. Make sure your motor is in good condition and is leaking as little as possible. Two stroke engines typically put half of their fuel into the water. Be careful when fueling your motor. Check rubber hoses for leaks. Regularly service your motor. Use propylene glycol instead of ethylene glycol for antifreeze. 7. Have a personal flotation device (PFD) for everyone in your boat. Children under the age of 12 must be wearing a PFD 8. Your boat must be registered with the State of NY. 9. It is illegal to drive a boat or personal watercraft under the influence of alcohol.

Fires - Be very careful of campfires and only build them in designated protected areas. Before you leave be sure your fire is completely out. We have had two major fires on Lincoln Pond that have destroyed acres of wildlife habitat.

Noise - There are other campers on the lake that can hear your “music” and “laughing.” We are glad that you are enjoying your stay; please let us enjoy ours as well. Please turn the volume down after 10 PM.

Litter - It is illegal to dump any material into the waters of NY. Please find the appropriate receptacle at the State Campgrounds or elsewhere.

Loons - We have a pair of loons that come back to Lincoln Pond every year. However, they have a hard time making it through the nesting period, which is the most vulnerable part of their life cycle. Loons usually nest within a foot or two of the water and will leave their nest whenever they feel threatened by waves. “We are finding that loons can nest on busy lakes as long as they have a quiet area,” says Eric Hanson, biologist for the Vermont Loon Recovery Project. In Lincoln Pond loons nest in Big Bay, which is the northern bay just before the narrows, in May and June. It is best to prevent boat wake in that area during nesting.

Tee shirts We are developing a Lincoln Pond tee shirt to help support the cost of some of the association’s activities especially the litter clean up and the milfoil control. If you are interested in obtaining a tee shirt for $15, please contact Judy Swartz at [email protected].

Thank you for your help in protecting our lake. Lincoln Pond Association Lincoln Pond/Milfoil 2002 Report 31

For Nita’s Notes

Milfoil, Moth larvae and Sunfish For the past two years, Robert L. Johnson (CURP), and his team have been working with the Lincoln Pond Association, Cornell Cooperative Extension of Essex County and the Lake Champlain Basin Program to try and find a way to control Eurasian watermilfoil, through biological methods. There are several herbivorous insects that feed on milfoil including the milfoil moth, the milfoil weevil, midges, Caddisflies and Mayflies. In the laboratory both the moth and weevil have been shown to provide various levels of control for milfoil. In larger lakes, we have seen natural declines of milfoil due to moth and/or weevil herbivory. In 1999, the Lake Champlain Basin Program provided a grant to see if the small natural population of milfoil moth in Lincoln Pond could be augmented to a level that would control a milfoil infestation of about 200 acres. In 2000 and 2001 over 60,000 moth caterpillars were released in an attempt to establish a large enough population to control the milfoil. Control seems to be effective when about 7 of 10 tips that are sampled have moth larvae feeding on them. We found that sunfish were eating our greenhouse-raised caterpillars before they had a chance to become established and as they moved up the plant to build a new retreat/house. This is a very disappointing finding. The milfoil is doing fine, the sunfish are doing fine, but the moth larvae are disappearing. Sunfish are found in large numbers in many small New York lakes. They are a warm water fish that does well when there not a lot of larger predator fish to eat them. Sunfish reproduce in large numbers and grow quickly. They compete for the same food supply as all young fish thus reducing the predator fish early growth rates. The most common types of sunfish are bluegills and pumpkinseeds. They eat insects such as mosquitoes, dragon fly nymphs, midges, caddisflies, and now we suspect milfoil moth larvae and milfoil weevils. Even the young of the year, one inch in size, were found chowing down on our larval caterpillars. Bill Schock of NYS DEC says that there is not much that can be done to control sunfish. Our best bet is more large bass in the lake to eat the sunfish and reduce their numbers. I am sure that the fisherman would like that option. A possible way to achieve is a catch and release program for bass. Almost all small fish in a lake eat insects. However, there are a few species of fish that eat fish once they grow large enough to get their mouths around the prey species. This includes: Bass, Pike, Muskies, Walleye, Lake Trout, and Brown Trout. Rainbow and Brookies eat insects their whole life. Lincoln Pond has Bass, Pike and Tiger Muskies. The other predator species are found in colder waters and larger lakes. The Tiger Muskies are self-limiting as they are territorial and will attack each other when populations become high. The problem is that it takes predator fish a long time to grow big enough to eat other fish and until then they must compete with the sunfish and other young fish for the same food source, including our insects. It looks like we will have to go back to the drawing board for new, environmentally friendly ideas for controlling milfoil in smaller warm water lakes. We have seen that milfoil in larger lakes might be controllable by the moth larvae and weevils, as they have more of the large predator fish, that control sunfish populations. However, that has yet to be proven. In Lincoln Pond/Milfoil 2002 Report 32 nature where the moth has been successful, it has always been in a larger lake or in a lake without sunfish.

Lincoln Pond Radio Tape Year three of the Lincoln Pond project has seen the best results so far for milfoil control by herbivorous insects. We tried releasing the moth larvae several different ways to see what method might have the best result. First we released them small and early, near the bottom of the plants, thinking that they would eat a lot of plants and we might see something the first year. But we were wrong. We never saw them again. Then we tried releasing larger moths later in the season and up in the vegetative portion of the plants. We could see some remnants of their eating and retreat building, but no moths two months later. Next we released cocoons, but could not find many of them either. Then that fall we released some dormant caterpillars in the resting phase. Amazingly, the next spring the milfoil was growing poorly at that site. Upon our examination we found the biomass and total tip length of milfoil was half of that in the control area nearby. This was very heartening. We are currently thinking that sunfish may have had something to do with the disappearance of our caterpillars. The dormant caterpillars may have survived because they would have crawled out of the mud when the milfoil was all bunched up on the bottom and the fish would have a harder time finding them. We hope to release even more of these dormant caterpillars in 2004, to further check our hypothesis. If you would like to know more about this biological control project for milfoil that was sponsored by the Cornell University Research Ponds and the Lake Champlain Basin Program contact me at 518-962-4810.

Sunfish and Milfoil Moths Small fish typically eat insects. Sunfish tend to swim in place and look for insects on plants where they pluck them off of the stem. Bass and trout also eat insects when they are small, but they are swimmers and move through the water to seek swimming insects. We believe that the Lincoln Pond sunfish (which are stunted from such high populations) are eating our moth caterpillars when we release them. Therefore the Lincoln Pond Association is looking for an effort to take as many sunfish as possible this summer. We are also asking fisherman to voluntarily release any bass that they catch, as the larger bass are very good at eating sunfish and will help to get the lake into a sustainable balance of large and small fish. An added bonus will be some very large trophy size bass in a year or two. If you would like to know more about this biological control project for milfoil that was sponsored by the Cornell University Research Ponds and the Lake Champlain Basin Program contact me at 518-962-4810. Lincoln Pond/Milfoil 2002 Report 33

Appendix LP 2002 – 6 Chart of actions

Site A B C D Plot EE Plot FF Plot B1 Plot B2 in D in D in B in B Control/ Control Control Control Control 6/14/00 6/14/00 6/22/01 6/22/01 Release 1-2 1-2 3-4 3-4 Age instar instar instar instar # 5,000 5,000 2,200 2,200

Before 3/yr 9/yr 0.25/yr 0.5/yr average moth # Before 9/yr 9.5/yr 21.75/yr 21/yr average weevil # After 2/yr 0/yr 1/yr 1/yr average moth # After 29/yr 23/yr 4/yr 3/yr average weevil # Before 20.81 31.11 59.43 69.22 biomass Gm D W milfoil After 66 58 25 biomass Gm D W milfoil