Fundamental
Concepts
Biocomplexity
Integrated Models
Social
models
Physical
models
Integrated
Models
Biological
models
Instream Flows for Recreation
1.
2.
3.
4.
How much water is needed for different
types of recreation ?
Impacts of swimmers on water quality?
Overlap of swimmers and aquatic organisms
River Road Connectivity
Instream Recreation, Luquillo Mountains, PR
1.6
Hydro-massage
1.4
H
H
H
1.2
Velocity, m/s
H
1.0
H
0.8
0.6
W
Waiding
Swimming
W
W
0.4
W
W
W
0.2
S
W
W
W
W
W
S
WAD
W
Shrimp
W WW WW
W
0.0
0
10
S
W
WW
S
S S
W WW
AN
WW W S W S
W W W
W
J J
S S
S
20
30
40
50
J
J
60
S
S
70
Jumping
J
80
J
90
100
110
Depth, cm
Little overlap in habitats used by aquatic species and humans
Aquatic species tend to migrate at night
Humans recreate during the day
Are the sites where people recreate
vulnerable to increases in turbidity?
35
El Verde
turbidity (NTU)
30
25
Hypothesized relationship
20
Las Vegas
15
10
5
0
0
50
100
150
200
number of people
250
300
350
Outcomes on Turbidity


Visitors do not select sites with stream beds
dominated by fine sediments (mud), and
therefore increasing visitor use at these sites
does not significantly increase turbidity.
Adjacent land use activities can have a
significant effect on deposition of fine
sediments in streams.
Role of Harvest on Aquatic Populations of
Shrimp, Crab, Lobsters & Fish




While it appears that non-consumptive recreation
use may not have a significant adverse impact on
aquatic populations, harvesters may have
The amount of extraction for personal and
commercial purposes is not well known
Extraction is legal outside of CNF but not within
To better model aquatic species diversity we need to
account for harvest.
Focus Group with 22
Fishermen






Fish the Río Espíritu Santo most
On average, fish 7 days/month year round
Use hooks, traps, and nets
Average catch of shrimp and fish is 4.6 lbs. per outing
Average size
 Shrimp: 5.5 inches
 Fish: 8.7 inches
Release gravid shrimp
Species Most Often Caught
(times mentioned by 22 fishermen)
16
10
14
9
13
8
7
12
6
3
Fishermen
Based on accompanying
1 fisherman in El Verde
on the Río Espíritu Santo


Nacillas: 3.7 shrimp
per hour on average
Sizes:



Minimum: 35 mm CL
Maximum: 105 mm CL
Average: 68 mm CL
Current Observations


Fishing continues within and outside the
Caribbean National Forest sometimes
independent of road access
Rates of harvest remain largely unknown
Future Research


Oral history of shrimpers
Interviews
River - Road Connectivity
Multi-scale variables derived with GIS can
predict important stream biology and physical
habitat characteristics that are influenced by
River-Road Connectivity
Role of road proximity, hillslope, and riparian
vegetation on river – road connectivity