LUQ DATA SET METADATA

Completed

Data Files and Variables

Data File Identifier Data File Collected
The number and mean lengths of shrimps from trapping ~2 weeks after the poisoningThe number and mean lengths of shrimps from trapping ~2 weeks after the poisoning
text/plain iconpoisshrimps.txt
 03/26/1999 - 03/28/1999
Physical and biological parameters from 10 survey pools and 10 survey riffles ~2 weeks after the poisoning
text/plain iconpoissurvey.txt
 03/26/1999 - 03/28/1999
Biological parameters from experimental pools ~2 weeks after the poisoning
text/plain iconpoisexperiment.txt
 03/30/1999 - 04/06/1999

Project

149
Effects of a tropical stream poisoning: do they reflect effects of small-scale experiments?

Abstract

Small-scale experiments in tropical streams have suggested that freshwater shrimps play a critical role in determining the quality and quantity of benthic organic matter and overall nutrient dynamics. We quantified the effects of a whole-reach shrimp poisoning event in the Sonadora, a second-order stream draining the Luquillo Experimental Forest in northeastern Puerto Rico. The illegal poisoning (for shrimp harvest) caused massive mortality of shrimps and aquatic insects. Atyid and xiphocaridid shrimp abundances in pools of the poisoned reach were reduced by ~95%, relative to abundances in an upstream reference reach. A survey of poisoned vs. reference pools, combined with a manipulative experiment (in which atyid and xiphocaridid shrimps were added to 3 poisoned pools), showed that reduced shrimp abundances due to the poisoning had strong impacts on benthic resources. The benthos of poisoned pools, where shrimp abundances were reduced, had 4 times more chlorophyll a, 6 times more algal biovolume, 4 times more fine particulate organic matter, 14 times more fine particulate inorganic matter, 5 times more carbon, and 4 times more nitrogen than did the benthos of pools in the reference reach. These increases in benthic resources were consistent with increases in algae, organic/inorganic matter, and nutrients in previous small-scale shrimp exclusion experiments conducted in the study river and tributaries. Effects of shrimp poisoning on the benthos varied by habitat, with riffles showing fewer significant differences than did pools. Compared to reference riffles, poisoned riffles had higher standing stocks of fine particulate inorganic matter, nitrogen, and biovolume of filamentous algae, and lower epilithic C:N ratios. Overall, previous small-scale exclusion experiments were highly predictive of the direction of effects due to large-scale shrimp removal by poisoning. Our study provides a tropical data set to add to the short list of stream studies that examine the predictive power of small-scale experiments for larger scales.

Owner:

Catherine Pringle

Contact(s):

Effie A. Greathouse

Associated:

Effie A. Greathouse
Nina Hemphill
Ernesto Garcia
William H. McDowell
James G. March
Alonso Ramirez

Researcher's Keywords:

LUQ
Luquillo

LTER Core Area(s):

disturbance

Complete Metadata:

  • Effects of a tropical stream poisoning: do they reflect effects of small-scale experiments?

    The basic information about a dataset

    Basic Information

    Program: 
    Luquillo LTER
    Luquillo Investigator Research
    Numeric Dataset ID: 
    149
    Data Set Identifier: 
    Effects of a tropical stream poisoning: do they reflect effects of small-scale experiments?
    Duration: 
    Completed
    Abstract: 

    Small-scale experiments in tropical streams have suggested that freshwater shrimps play a critical role in determining the quality and quantity of benthic organic matter and overall nutrient dynamics. We quantified the effects of a whole-reach shrimp poisoning event in the Sonadora, a second-order stream draining the Luquillo Experimental Forest in northeastern Puerto Rico. The illegal poisoning (for shrimp harvest) caused massive mortality of shrimps and aquatic insects. Atyid and xiphocaridid shrimp abundances in pools of the poisoned reach were reduced by ~95%, relative to abundances in an upstream reference reach. A survey of poisoned vs. reference pools, combined with a manipulative experiment (in which atyid and xiphocaridid shrimps were added to 3 poisoned pools), showed that reduced shrimp abundances due to the poisoning had strong impacts on benthic resources. The benthos of poisoned pools, where shrimp abundances were reduced, had 4 times more chlorophyll a, 6 times more algal biovolume, 4 times more fine particulate organic matter, 14 times more fine particulate inorganic matter, 5 times more carbon, and 4 times more nitrogen than did the benthos of pools in the reference reach. These increases in benthic resources were consistent with increases in algae, organic/inorganic matter, and nutrients in previous small-scale shrimp exclusion experiments conducted in the study river and tributaries. Effects of shrimp poisoning on the benthos varied by habitat, with riffles showing fewer significant differences than did pools. Compared to reference riffles, poisoned riffles had higher standing stocks of fine particulate inorganic matter, nitrogen, and biovolume of filamentous algae, and lower epilithic C:N ratios. Overall, previous small-scale exclusion experiments were highly predictive of the direction of effects due to large-scale shrimp removal by poisoning. Our study provides a tropical data set to add to the short list of stream studies that examine the predictive power of small-scale experiments for larger scales.

    Short name: 
    LUQMetadata149
    Project Title: 
    Core Area: 
    disturbance
    Researchers´ Keywords: 
    LUQ
    Luquillo
    2006 Proposal Classification: 
    Stream ecology
    Table 4 Long-Term Classification: 
    disturbance
    stream channel change
    Station Acronym: 
    LUQ
    Data File Structure Referrer: 

    Georefs, Dates

    Publication Date: 
    06/07/2011
    Collected: 
    03/26/1999 - 04/06/1999
more