01970nas a2200205 4500008004100000245005100041210004900092300001200141490000700153520141000160653002101570653001401591653001001605100002001615700001801635700002301653700002001676700001901696856004901715 2008 eng d00aFish Movement Among Lakes: Are Lakes Isolated?0 aFish Movement Among Lakes Are Lakes Isolated a577-5880 v153 a

The concept of a lake as an isolated unit is a central theme in research and management of freshwater systems. Support is based on direct observations of lake communities. Studies undertaken in the last several decades lend tacit support because the methods used in both research and management often do not question the underlying notion that lake communities are essentially isolated. In a study of fish assemblages in interconnected lakes, we noted movement of tagged fish among lakes. We also found that species introduced to one lake were later captured in neighboring lakes. We found that fish species in lake assemblages did not differ from those in inlet and outlet stream assemblages; although relative abundance varied, species richness and composition did not. This finding suggests that fish assemblages in lakes are not isolated. Rather, immigration and emigration from streams and other lakes occurs. Although few individuals migrated to new lakes, any movement can affect population structure (e.g., through recolonization, gene flow) and management goals (e.g., spread of disease). Consequently, we suggest that methods commonly used to assess fish assemblages in lakes and the concept of the lake as a management unit may need to be reconsidered. Rather than be treated as isolated populations, fishes in lake communities may be better treated as a watershed-wide metapopulation.

10afish assemblages10aisolation10alakes1 aDaniels, R., A.1 aMorse, R., S.1 aSutherland, J., W.1 aBombard, R., T.1 aBoylen, C., W. uhttp://dx.doi.org/10.1656/1092-6194-15.4.57702687nas a2200253 4500008004100000245010400041210006900145490000700214520193400221653001202155653001902167653001002186653002002196653001502216653001902231653001302250653001802263100002002281700001702301700002802318700002202346700001802368856004702386 2001 eng d00aResponses of Onondaga Lake, NY to early stages of rehabilitation: unanticipated ecosystem feedbacks0 aResponses of Onondaga Lake NY to early stages of rehabilitation 0 v733 a

Responses of polluted Onondaga Lake, New York, to early stages of a phased program to rehabilitate the lake from the effects of domestic waste inputs are documented. The analysis is based on more than 10 years of paired monitoring of the effluent (total ammonia and total phosphorus) of a wastewater treatment plant (WWTP) that discharges to the lake as well as the lake itself (including total ammonia, nitrite, total and dissolved forms of phosphorus, plankton biomass and composition, Secchi disc transparency, and zebra mussel density). Major reductions in total ammonia and total phosphorus loading relative to the preceding decade are reported for the WWTP for the November 1998 through October 1999 interval. Dramatic and, in some cases, unanticipated changes in the lake's water quality and biota in response to the reductions in loading are documented for the April to October interval of 1999 including: (1) major decreases in total ammonia concentrations and improved status with respect to ammonia toxicity standards, (2) development of dense populations of zebra mussels, (3) decreases in fall concentrations of nitrite and improved status with respect to the related toxicity standard, (4) decreases in total phosphorus and total dissolved phosphorus concentrations, and (5) a severe Microcystis (phytoplankton) bloom that caused nuisance conditions and poor clarity. The zebra mussel invasion is attributed to the reductions in total ammonia concentrations to below toxic levels. The Microcystis bloom was probably related to the abrupt increase in the zebra mussel population. Additional reductions in phosphorus loading from the WWTP will be required to limit phytoplankton production and avoid the potential for continued nuisance conditions. Potential complications in resolving lake responses to future reductions in loading associated with the zebra mussel invasion are considered.

10aammonia10aeutrophication10alakes10anuisance blooms10aphosphorus10arehabilitation10atoxicity10aZebra mussels1 aMathews, D., A.1 aEffler, S.W.1 aBrooks), C., W. Mathews1 aSiegfried, C., A.1 aSpada, M., E. uhttp://dx.doi.org/10.2175/106143001X14343901680nas a2200205 4500008004100000245009300041210006900134300001200203490000600215520102300221653002001244653001701264653002901281653001001310653002101320100002101341700002201362700002001384856007001404 2001 eng d00aDistributions of Lake Fishes in the Northeast-IV. Benthic and Small Water-column Species0 aDistributions of Lake Fishes in the NortheastIV Benthic and Smal a455-4820 v83 a

Using data collected at 203 randomly selected lakes in eight states in northeastern USA, we present maps of distributions and native status for 28 fish species: 15 benthic species in five families, 11 small water-column feeders in six families, and two large piscivores. Brown bullhead and white sucker were among the most widespread lake-dwelling fishes, and were collected in 69% and 56% of the sampled lakes. Banded killifish, American eel, and yellow bullhead were collected in 26%, 19% and 17% of sampled lakes respectively. The remaining species were collected in <8% of the sampled lakes. Many of the species that were uncommon in this survey have limited distributions in the Northeast or are more commonly found in streams than in lakes. Seven species discussed in this article are Mississippian and were only collected in Cross Lake, NY. We also present a summary of the extent, geographic distributions, and native status of all 88 fish species collected in the EMAP – Northeast Lakes Project.

10abenthic species10afish species10ageographic distributions10alakes10anortheastern USA1 aWhittier, T., R.1 aHalliwell, D., B.1 aDaniels, R., A. uhttp://dx.doi.org/10.1656/1092-6194(2001)008[0455:DOLFIT]2.0.CO;201570nas a2200217 4500008004100000245007800041210006900119300001200188490000600200520087500206653001701081653005201098653001001150653002201160653001801182653002101200100001901221700002201240700002001262856007001282 2000 eng d00aDistributions of Lake Fish in the Northeast: II. The Minnows (Cyprinidae)0 aDistributions of Lake Fish in the Northeast II The Minnows Cypri a131-1560 v73 a

We discuss the distribution and native status of 24 minnow species (family: Cyprinidae) collected at 203 randomly selected lakes in the northeastern USA (New England, New York, New Jersey) by the Environmental Monitoring and Assessment Program (EMAP). Twenty-four species were collected during the summers of 1991–96. Only golden shiner was frequently collected, occurring in 71% of the sampled lakes. Fallfish, creek chub, and common shiner were also common. The remaining species were taken in <10% of the lakes. Physical (surface area, depth, elevation), chemical (pH, total phosphorus), and watershed disturbance characteristics of the lakes show distinct species-specific patterns. Evidence suggests that native minnow biodiversity has declined over the last 150 years as a result of changing biotic, physical, chemical, and watershed characteristics.

10adistribution10aEnvironmental Monitoring and Assessment Program10alakes10aminnow Cyprinidae10anative status10anortheastern USA1 aWhittier, T.R.1 aHalliwell, D., B.1 aDaniels, R., A. uhttp://dx.doi.org/10.1656/1092-6194(2000)007[0131:DOLFIT]2.0.CO;2