Thursday, January 6, 2011

CFZ Firefly Survey Bakam and Sg Raan 06th Jan 2011

Nighttime Assessment of Fireflies at Sg Bakam and Sg Raan:
06th Jan 2010

Observers :
Musa, Sara, Nazeri, Joyce, Remli , Pak Juji's son (boatman).

Jety/Berth Location: Bakam River Juji House Jetty 4°14'36.98"N 113°55'43.99"E Raan River Tamu Jetty 4°14'47.08"N 113°55'27.82"E


Sg Bakam


Sg Raan

We took off at 18:40 from Juji House jetty
Field work
START Time: 18:40
Field work FINISH Time: 20:18

PHYSICAL CONDITION:

a. MoonPhase :
6 moon day, moon not seen cloud covered.

b. WeatherDrizzling, slighty windy, however raining stopped when we survey Sg Raan.
Relative Humidity: 86%
Water temperature not taken
Air temperature 27.1 ° C
Water pH : 6 at Both River
Specific gravity: At jetty 1.004 at Juji Jetty, 1.000 at end of Raan
Wind : Slight Wind, a little breeze
No Haze

c. River ConditionCurrent: Slow rising tide, Whitish sediment.
Boat used: Yamaha 40 hp.
Survey Average Speed 4.0 Km/hr.
Tide: going up
Notes:

We decided to do Sg Bakam first considering the short distance of boat travel involved ie. slightly more than 1.2 km. The river is clean, of whitish sediment runoff, very small and shallow.

Along the banks were several grassy areas but most were orchards's belonging to the villagers scattered along the river. There were also several houses built on the bank of the river right at the edge. There were no mangroves recorded along Sg Bakam at this stage.

All along our traverse, we recorded presence of rover fireflies and two trees that harbored a group of fireflies of about 10-20 rovers. These were not the congregating types.

Just before the Sg Bakam concrete bridge we recorded a juvenile crocodile between vegetation by the riverbank. We have been informed earlier by Pak Juji of the presence of a large crocodile specimen of 6ft girth in Sg Bakam, it was seen basking at the estuary several months back.

We surveyed until 1.2 km of Sg Bakam from the bridge.

After Sg Bakam we reconvened at the Kg Bakam Tamu to board another boat to survey Sg Raan. Sg Raan and Sg Bakam share the same estuary. While Sg Bakam traverses inline, Sg Raan meanders gently along the coast before traversing inline after an almost 90 degree turn inland.


Musa and Joyce taking measurements from the water sample.


One of the several productive display trees along Sg Raan, mangrove apple tree.


A few samples from the nite glowing brightly, greenish hue. The population here seems larger than the one we've seen elsewhere before, it would be interesting to get them id.

We entered the Sg Raan and immediately saw our first display tree at WPT 414 at 19:28. On previous late night visits here between 10:30pm and 11:30pm, we did not notice any fireflies. Musa had been to this bridge twice previously but late at night and didn't noticed any presence of fireflies. Perhaps this again support the notion that the peak firefly display occurs only between sunset to 8:30pm.

We saw many display trees along the river after the Kampung Kuala Bakam, along the Melanau settlements by the rivers edge. The river was scattered with large sea worthy fishing boats belonging to the villagers.

We recorded a high abundance of display trees after the Hawai Beach wooden bridge. Visual estimates put the numbers to between approximately 50 but upon sweeping with our capture nets, we were surprised with actual number of fireflies exceeding that initial estimates by about 3x. Most of the fireflies were flashing away underneath the leaves of their host trees. Some already with mates were there too hidden from view. We collected several good male samples along this traverse for later identification.

We stopped the survey after a 2.2 km traverse when the river became significantly narrow which does not allow our largish boat to enter. We took a bottle of water as a sample sample and headed back to the jetty.

Our boat driver recorded sightings of 4 crocodiles, we only made two visual contacts. One was a juvenile and the other a sizable young adult with very bright eyes. Our driver informed us that he was aware of cases of illegal crocodile hunting for the Chinese restaurant market in Sg Raan.

On hindsight, we had probably missed the peak display period of the Sg Raan congregating fireflies by starting the survey at Sg Bakam first. We can safely say that most of Sg Bakam is in a degraded state as afar as fireflies are concerned. Sg Raan however is still lined with nipah, pedada and bakau, ideal haunts for these little beetles.

Having said that, the situation at Sg Raan can only go downhill for these fireflies without further measures being taken to halt any related riverside development along it's banks. Without a doubt present fishermen settlements along the river has taken down with it a few display trees already in the past.

The group of the berembang trees after Hawai Beach bridge deserves to be protected for the healthy number of display trees as well as large numbers of displaying fireflies found there.



Bakam River
WPT Time Co-ordinate Fauna Side Counts Remarks
407 18:56 N4 14.728 E113 55.644 F L 2 Roving fireflies at Bamboo tree
408 18:59 N4 14.608 E113 55.649 F L 1 Roving
409 19:00 N4 14.613 E113 55.684 F L 1 Roving low
410 19:05 N4 14.598 E113 55.839 F L 1 Roving high
411 19:05 N4 14.586 E113 55.842 F L 10 at Bamboo tree
412 19:06 N4 14.555 E113 55.841 F R 1 roving
413 19:06 N4 14.552 E113 55.848 F L 10 at Bamboo tree
2 display trees and roving fireflies

Raan River
WPT Time Co-ordinate Fauna Side Counts Remarks
414 19:28 N4 14.952 E113 55.517 F L 10 Nipah
415 19:28 N4 14.966 E113 55.521 F L 20 Nipah
416 19:32 N4 14.986 E113 55.520 F L 10 Berembang
417 19:34 N4 15.046 E113 55.563 F L 20 Mangrove
418 19:34 N4 15.052 E113 55.573 F L 20 Berembang
419 19:37 N4 15.062 E113 55.587 F L 10 Berembang
420 19:38 N4 15.096 E113 55.616 F L 20 Nipah
422 19:48 N4 15.519 E113 55.846 F L+R 50 Nipah tree colony
423 19:49 N4 15.533 E113 55.861 F L+R 50 Nipah tree colony
424 19:53 N4 15.545 E113 55.865 F R 50 Nipah tree colony
425 19:55 N4 15.571 E113 55.879 F L 1
426 19:56 N4 15.597 E113 55.895 F L 1
427 19:56 N4 15.609 E113 55.902 F L 50 Nipah
428 19:57 N4 15.618 E113 55.915 F R 20 Bakau
429 19:59 N4 15.626 E113 55.918 F R 50 Berembang
430 19:59 N4 15.634 E113 55.926 F L 50 Nipah
431 19:59 N4 15.646 E113 55.941 F R 50 Berembang
432 20:00 N4 15.658 E113 55.957 F L 100 Berembang
433 20:01 N4 15.675 E113 55.973 F L 50 Berembang
434 20:01 N4 15.680 E113 55.976 F L 100 Berembang
435 20:02 N4 15.700 E113 55.993 F L 1 Rover
438 20:18 N4 15.001 E113 55.517 C R 1 Large
18 display trees, 4 roving fireflies

Note:
F=fireflies
C=Crocodiles
L=Left side of the river according to direction of travel
R=Right

We collected several samples along Sg Raan:
WPT 415 male 2 female 2
WPT 418 male 1 female 2
WPT 420 male 2
WPT 423 male 8 female 2
WPT 428 male 3 female 1

Collection of the males will help us tremendously in identifying the firefly species at Sg Raan.

Article by Musa Musbah and Nazeri Abghani;
Images by Sara Wong;
Maps and tracks by Musa Musbah

MNS Miri Branch CFZ/Jan 2011

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