Hello all, Just thought
I would relay some of my collecting notes from this weekend. Later,
I will write up a description of the terrain since understanding
the terrain is necessary to understanding the aquatic
habitats.
Sat. 2
Sept. 2000.
From Caracas we traveled south down the Cordillera
de la Costa towards the Northern Llanos. Basically, this
journey brings you down from the mountains to the large
flat plains known as the Llanos. Several rivers drain
south down these slopes into the mighty Orinoco. I drove
as far south as El Sombrero in the Northern Llanos. Unfortunately,
since it is still the wet season, I found collecting
here impossible. These flooded plains are just saturated
mud at this time of year and it is impossible to get near
any water without sinking dangerously deep in the mud.
I attempted collecting in one roadside creek and quickly
found myself knee deep in the mud and stuck. The mud was
so thick that it literally sucked one of my sandals off
of my foot. This made me mad as these were my collecting
sandals which I have always used, collecting from the
States to Ecuador. At this point I decided to leave
the Llanos until the dry season and headed north back
into the mountains.
The next collecting location was the Rio Pao just outside
of San Sabastian. The Rio had a small amount of current
and was muddy brown with sediment (as are most rivers
in the wet season). The water temp was near 80F and the
Rio was about 15-20 feet wide. The typical depth was 6-12
inches with deep areas near cutbanks. By running a four
foot by four foot seine along the shallows I was able
to collect wild guppies and a number of cichlids. I seined
the outside cutbanks where there were many overhanging
land plants and managed to collect a fair number of Farlowella.
The water was about two feet deep on the outside banks. Also
collected was a small (2 inch) Hypostomus sp. This
fish was collected from the center of the creek in the
strongest rapids by basically pure luck. It got caught
in my net as I was crossing the river. I continued
up the mountains towards Caracas and stopped to sample
the Rio Zuata in the village of San Casimiro. The collecting
site was beautiful. A crystal clear mountain stream with
a bed of fist-sized rocks. By seining near the banks I
turned up pike cichlids, Hoplias, and a small species
of tetra. In the main rapids I was able to collect a Chaetostoma
sp. by kick seining. Although this was the most beautiful
place to collect, it was also difficult. In the clear
water the fishes could see me from far away and scatter.
I saw many loricariids (sp. unknown) scramble away
from me. I plan to try this site again with a 12 seine
which should work much better.
Mon. 4 Sep.
2000.
On Monday I headed east out of Caracas through the towns
of Guatire and Caucaqua. There were beautiful rivers, but
they were still too full of mountain run off to attempt
to collect from. At this point I headed west towards Santa
Teresa along the Rio Tuy. Just outside of Santa Teresa I
collected at a spot where a creek enters the Tuy. The beautiful
creek was unproductive so I kept moving towards the juncture
of the creek and river. The silt from the creek was piled
high at the juncture and I sunk 3-4 inches deep with every
step. The mud flats also smelled to high heaven! Surprisingly,
seining the mud flats was very productive. Every net (4
ft by 4 ft seine) brought up 2-3 Corydoras aeneus. All
fish were adults of about two inches. I retained 5 for myself. Interestingly,
Caracas is listed as the collection location of the holotype
of C. aeneus. My guess is that the holotype
was collected in the Rio Guaire which flows through Caracas.
However, this river is now so polluted that no fish could
live in it. The Guaire flows out of Caracas and joins the
Tuy. Since I was collecting C. aeneus as close to
the Guaire as it is possible, it should be as close as is
possible to the actual holotype of C. aeneus. Corydoras
aeneus from the wild are beautiful! They are a true
bright metallic bronze color. You have to have collected
this fish from the wild to know what I mean about the color.
The last highlight of this spot was that I collected a huge
(7-8 inches SL) Hypostomus. This fish was collected
against the mud bank at the confluence of the creek and
the river. Several small cichlids were collected as well,
but no tetras. This past Saturday (9 Sep 2000) I headed
south to Embalse Camatagua about 1.5 hours from Caracas.
Camatagua is a huge reservoir famous for peacock bass (various
Cichla spp. and not Bass at all) fishing. I scouted
out the area where the Rio Guarico exits the lake and it
was teeming with fish. The main problem with collecting
there was that the river is choked with aquatic vegetation. The
vegetation is mainly Elodea, but there are many other species
of plants growing here. I headed south along the lake to
a small creek not on the map. The creek appears to
be a small tributary of the Rio Camatagua and is referred
to by the locals as Quebrada Camataguita (translation: little
Camatagua stream). A bridge crosses the stream and
provides a nice collecting location. Two small boys
were on the bridge fishing with a tiny hook and what looked
like large bloodworms for bait. They had collected a cichlid
lovers dream with their little hooks. Most of their catch
were large tetras, Acara, pike cichlids, and what
appeared to be Biotodoma and Festivums. There
were also spp. of cichlid that I could not identify and
Hoplias. Collecting the stream with a 4 foot seine
turned up numerous species of cichlids and tetras. The catch
of the day was a small Rineloricaria-type loricariid
about three inches in length. There were also various Leoprinus-looking
fishes that proved too fast to capture. I came across one
large (six inch) Hypostomus species but could not
catch it. The fish kept moving around a large rock in the
middle of the stream and I kept chasing it around the rock,
but the pleco was always faster than I.
Also, at this location I caught some large (2-3 inch) freshwater
shrimps. The water in this location was crystal clear with
a stream bed of gravel and small rocks. The stream was 4-6
feet wide in the riffles with a pool every 10-15 feet. The
pools were 15-30 feet in diameter and from 2-4 feet deep.
They were home to the various cichlids and many tetras.
Other tetras, pike cichlids, loricariids, and hoplias
were also found mainly in the riffle sections. The water
was very warm (about 80F) except in a few shaded pools that
were no longer connected to the main stream. These pools
turned up guppies, a few small cichlid fry, and a young
Hoplias about 2 inches long. The temperature in the
shaded pools was about 76F. I took video footage of
the stream and the fishes collected before returning them
to the creek.
I hope to return to this location soon with a scuba mask
and a large hand net in hopes of snorkeling the pools and
collecting from them. They are too deep to be
collected with a small seine. I also am convinced that I
need to modify my nets with larger heavier weights on the
bottom. Since so many loricariids stay so close to
substrate, they often swim right under my net. Hopefully
larger weights will better anchor the net to the substrate
and prevent some of this.