Banca de DEFESA: MARCELO CAMARA RODRIGUES

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : MARCELO CAMARA RODRIGUES
DATE: 29/07/2022
TIME: 14:00
LOCAL: Google Meet
TITLE:

Reproduct biology, habitat use and social structure in Cyanocorax cyanopogon (Whaite-naped Jay)

KEY WORDS:

Seazonality; Occupation models; Animal social network; Corvidae;Caatinga.

PAGES: 49
BIG AREA: Ciências Biológicas
AREA: Ecologia
SUMMARY:

Although costly, group living is widely distributed in nature. Among birds, crows and ravens (Corvidae) stand out for their cognitive ability and for forming social groups that provide better performance in caring for offspring. Cyanocorax cyanopogon (White-naped Jay) are endemic to Brazil and occur mainly in Caatinga and Cerrado, two
biomes with strong seasonal component, alternating between periods of low and high productivity. In order to understand the strategies used by these birds to live in these biomes: 1) we will verify if they adjust their reproduction to the availability of resources in the environment; 2) we will analyze if the environmental characteristics and the availability of resources interfere with their occurrence in an area of Caatinga; and 3) we will describe the social structure of the groups of individuals that use the area of the FLONA-Açu. In our records of nests we found that the development of the nestlings lasts about 7 months, from the construction of the nest until they acquire adult plumage. Putting our reproductive records together with those available on Wikiaves and comparing them with the WorldClim precipitation data, we found that most of the records anticipate the month with the highest rainfall volume. We also found that this trend is stronger in the Cerrado than in the Caatinga. We compared 128 models generated from our global model with 8 environmental variables. Of the total, 5 models were the most representative. The most relevant parameters for occupancy were: season, distance from headquarters and NDVI (Normalized Difference Vegetation Index). In this model the occupancy estimate for the rainy period was almost half of what was observed in the dry period. Occupancy also varied positively as a function of NDVI and negatively as a function of distance from headquarters, both with greater effect in the rainy season. We captured and ringed 89 individuals at the headquarters of the Açu National Forest. However, between January and the end of July 2021, we revived only 42 of them. In these resightings were nestlings and some adults. The consistent resighting of a few individuals together is a strong indication that they maintain a family group formation within the study area. Our results from monitoring individuals in the headquarters area of the Açu National Forest showed that individuals form relatively consistent groups over time. We also verified that individuals ringed as nestlings, in 3 different years, remained together during this period. With the co-occurrence records we built a general network, from which we derived sub-networks, with records in the dry season and another with the rainy season records. The general and dry season networks showed similar density values (0.41 and 0.42, respectively) and modularity (0.43 and 0.40, respectively), but very different from that obtained for the rainy season (0.14 for density and 0.67 for modularity). These results indicate greater connectivity between individuals in the dry season than in the rainy season. This is associated with higher resource availability in the rainy season, which is also amplified by the reproductive period of the species.

COMMITTEE MEMBERS:
Externo à Instituição - PEDRO DINIZ ALVES - UnB
Externa à Instituição - ANGELICA MARIA KAZUE UEJIMA - UFPE
Externo ao Programa - 1476621 - DANIEL MARQUES DE ALMEIDA PESSOA - nullPresidente - 1439088 - MAURO PICHORIM
Interna - 3058386 - VANESSA GRAZIELE STAGGEMEIER